Happy New Year!

[junglejim]

I could be wrong but I believe our military trains snipers to be able to calculate range, trajectory, etc., for those same reasons. An equipment reliant sniper is just a dude with a rifle if the equipment fails.

Knowing HOW to do something and being ABLE to do are two different things. One comes from training and the other comes from experience. Both are important and in both activities to which you refer.