This kind of thing is more likely to happen in a shop less than ten years old or when the mechanics are younger guys. One inch steerers are seen much less often, disappearing from mountian bikes by around '94 and road bikes probably around 2000. Not everyone knows everything(And a .6mm difference in headset races is a good example of one of the annoying things about the bike industry). I know old school guys that can swap a set of Campy G-springs in twenty minutes, but would have no idea how to rebuild a Fox F80 RLT.

Why anyone would set a fork on the ground to install the race is beyond me, just hold the fork at the crown. Same with pounding the crap out of... anything. If you hit it hard twice and it does not move, something is wrong.