[lolinder]

I think you're getting downvoted for the use of the word superficially (what he does and is impressive and the video you linked doesn't debunk the trick shooting itself except for the split arrow), but this is an important contribution. His historical claims struck me as off, and this video does a good job of explaining why.

"How did the Saracens measure seconds?" — My thought exactly!

[dan-robertson]

I think the claim is that surviving texts about training archers describe shooting an area is a certain distance and loosing two more before the first hits the ground (with some extra requirement that the first not be aimed at some high angle). You can then go back from the kinds of bows they had and turn that into an estimate.