Not all groups enjoy the thick fighting at the center of a solid line. Others lack the experience, numbers, or equipment to do so successfully. These groups often suffer at larger events, where the lines are densely packed. Skirmish tactics work a little differently when facing such lines, as opposed to the more open fields of their home practices. A skirmishing group needs to capitalize on their best asset: maneuverability.
A skirmish line will quickly be picked apart should they face a group of experienced line fighters directly, especially if numbers aren't in their favor. However, this doesn't mean skirmish lines are incapable of winning the fight. It takes a different approach for them to succeed. Rather than attempting to rush into a line fight, the skirmishers need to fight the front of the line on the defensive. Their main goal has to be survival, only taking advantage of a few kills as opportunity presents them. By keeping mobile, they might be able to get the enemy to spread out or lose track of a few of the skirmishers. By drawing the enemy directly ahead, a few people on the wings might be able to flank around the enemy.
While most people "flank" by merely running past the ends of the lines until they are far enough to get around unopposed, a little more teamwork and tactics can make flanking a much stronger, faster tactic. It is best to work in groups. Pairs work fine, but larger groups have more options. Each group must set for itself a goal of delivering one fighter (or small group of fighters) the enemy's back. This mindset allows flankers to function much closer to the core of the fight and still get someone behind the lines unopposed. As an added bonus, some of these tactics also apply to heavy line fighting for shock troops, which could help a group transition to that style of fighting later.
Let's look at a few specific strategies.
Pin and split
Pin and split is my generic term for a great move that you can accomplish when, as a flanker, you outnumber the enemy that is in your way. At its most basic, a 2v1 situation, one person engages the enemy, allowing the other to slip by unopposed. Regardless of how well the pin survives, they buy their teammate plenty of time to cause havoc. This strategy also works well for exploiting the edges of a gap in the enemy line.
Another extremely effective way to use this strategy is to counter flankers. If your own team's flankers have become bogged down on the flank, fighting a line battle, the two fighters nearest them could try to pin/split against the enemy anchor. The second closest to the end engages the enemy anchor heavily, probably fighting a 2v1 on the enemy flank. The friendly anchor is then free to backstab the enemy flankers, freeing up a large force. This is an exploit of the gap between the enemy line and their flankers, but could be used against almost any gap.
When outnumbered, but not outmaneuvered, a team can attempt to split up. By being more mobile than the larger force, their goal is to survive and pick apart any stragglers they can until the smaller force has a decisive advantage. The skirmishing team still needs a few people to take the enemy head on. When the enemy advances, the line spreads thin, leaving just a few fighters to keep the attention of the enemy core. The rest flank around, using strategies like the pin and split.
However, because the skirmishers are outnumbered, getting into the enemy backfield alive is going to be difficult, if not impossible, until several enemies are dispatched. If the skirmishers can manage to get their flankers to meet up behind the enemy (turning the line into a circle), they are now free to run in opposite directions. At this point, the skirmishers must work off of each other. By running in opposite directions, vision gaps will eventually be created that allow one of them to pick off an unsuspecting enemy.
A large part of the strategy requires that each skirmisher acts as a distraction first, staying alive as best they can. Then, only take shots that are nearly guaranteed hits. Kills are preferable, but legs will help reduce the enemy's ability to maneuver against you and arms will help soften them up for future attacks.
Small groups should learn to work in pairs when possible. The goal is to develop tactics that work well when targets are isolated, while maintaining some safety in numbers. While you won't always be able to make a 2v1 situation happen, you want to be able to win the fight without losing much of your capability.
You may find 2v1 drills particularly useful. It helps build teamwork for the pair and helps the solo fighter practice for being outnumbered. The pair has a goal of killing the solo without either of them being hit, while the solo tries to land a single hit on the pair. Alternatively, you could have the solo fighter try to stay alive for a set amount of time or number of swings. This can help them prepare to be a pin or to keep the core of the line busy for a wolf pack strategy.
One strategy for a pair is to plan, in advance, where to swing. For example, one will swing high to the sword arm, while the other swings low to the shield side hip. This forces the enemy on the defensive, because their shield will usually not be able to cover both angles, forcing them to block with their sword or die quickly. Following up with a couple of swings will likely kill the target, as long as both keep the pressure on them.
When the pair is on the defensive, it becomes important to not only block for your partner, but lure enemy targets out for them. You can fake swings to try to get the opponent to counter, leaving their arm open to your partner. Placing swings to one side of their shield or guard might draw their defenses over, letting your partner attack the other side.
Against a solo opponent, the pair needs to move such that both can swing at the target or so that neither can be hit easily. The most favorable positions for the pair are either with the solo fighter facing the gap between the them, or with the pair slightly offset towards the solo's sword side. This allows both to swing, and the latter gives a great angle against their weapon arm.
"Good" in this case, relative to the pair.
On the flip side, the solo fighters will need to use solid footwork and sword blocks/parries to stay alive. Most of their footwork will have them backing up, often to an angle. Against a pair, their goal is to isolate one of them by stepping away from the other. His preferred positions are either lined up against his sword side opponent (so his shield blocks off the other well), or with one enemy blocking off the other's angle of attack. The second one is harder to pull off, but is the safest.
I can never seem to stress this enough, but communication is vital to success as a small force. Even without a command structure or leader, the group needs to all be aware of the overall plan. Without communication, strategies like wolfpacking can quickly fall apart into chaos.
Experienced vets may be less verbal, relying on their combined experience and reacting to the situation as best they can. However, even vets will make sure to communicate openings they see or dangers around them. Starting out, simple communications like when to move or change spacing are necessary (vets usually adapt to the space well, without needing specific commands for it). One thing all groups need is a direction or target, and communicating that goal, or changes to it, should be a priority.
Call out dangers to your line. Call out targets, gaps, and weak points in the enemy line. Equally important, relay calls from others. For example, if you line needs to shift right, and you hear someone call it out, then you should repeat it down the line. Warn your allies of arrows about to be loosed, javelins at the ready, or support weapons taking notice of their flank. It is a lot to keep your mind on, but the more of these things you can keep your team informed about, the more successful they will be.
Leadership ("Driving the bus")
Smaller groups sometimes lack any sort of command structure. Even large realms have many people that could take charge, but no clear, default leader. That doesn't mean they lack leadership. In these groups, individuals usually take charge of the area around them as needed. Groups of veterans often have a very decentralized form of command, especially during a protracted line battle where individuals manage their own area. Those with the best line of sight, or that notice problems sooner, often begin taking charge of the few people around them.
If someone else is issuing orders, do your best to support them. Note, I didn't say "blindly follow a terrible plan". Support the plan by maneuvering yourself and others in a way to help the plan succeed. This might mean moving to cover a gap that no one else saw or being aggressive to draw the enemy's attention. Sometimes it means doing something that is opposed to the orders, such as taking a run through a gap rather than standing your ground. The overall idea is to make the group more successful at its current mission.
If no one is taking charge or communicating, take command and do your best to help the team. Even a bad plan is usually going to be better than no plan. When it comes to actually taking charge of the group, do your best to navigate the group into favorable fights. Try to issue orders that make sense for who you are ordering around, ie. don't have the 300 lb guy in full armor and a tower shield flank. Play to your group's strengths. More armored up fighters will need to form up against the bulk of the enemy, while faster fighters need to maneuver around. Try to engage targets such that your backfield is relatively safe (not facing the majority of the enemy groups).
Most of the fight relies on your individuals finding success, but issuing commands to regroup or shift the line can give those individuals a better chance to survive. Your goal, as leader, is to maintain the line during a fight. Watch for gaps and weak points in both lines and move your forces to exploit or counter them. Learn to spot vision gaps, especially along the enemy flank. If their anchors aren't paying attention or are drawn into a fight, deploy a few flankers around them. If your flankers need a better angle, shift the line to present the enemy's back to them.
"Driving" isn't easy, even in a small, skilled group. Don't be discouraged by a bad fight or if you think you may have made a bad call. Learn from the strategic failures and try to fix any issues with communication within the group. You'll get a chance to redeem yourself next fight.
One side note, when a small group is part of a large team, they should do their best to integrate with the group. Issue commands not only to your group, but those around you that lack leadership. This is a great opportunity for smaller groups to get a better feel for line fighting, and working with support weapons. Also, don't hesitate following orders from outsiders in this scenario, especially ones that seem to know what they are doing.
This section probably could be its own post. I might try to put together a more detailed version, perhaps as a post-mortem next time I drive the BOF bus.