Archers are discussed and tested in this thread. Particularly, post #21 in the thread is my findings from configuring some British Retinue Longbows in various formations and letting them fire on incoming HRE Armoured Sergeants.

Long story short, though, they killed a measly 4% more of the incoming unit when in a 2 line configuration, but no better in standard form than in 4-column form, though standard is considerably wider. I'm forced to conclude the formation has no appreciable impact on archer fire, and the slight better performance of 2-line vs. the others is due to an anomaly.

It may however have defensive or tactical implications:

- Archers in a very narrow formation can better fire into breaches and doors in enemy walls, as more of them have line of sight directly at an enemy unit visible through the hole. This allows them to choose a low trajectory instead of firing up and over the walls, and gets them more kills as a result.

- Obviously changing their front alters how they will interact with other units in melee combat. Any comments on the effects of formations on this would be most welcome.

- I'm sure there's more I just can't think of.