There is little reason to believe that humans are so good at matching from screens to reality that proper located AR information isn't better (in domains like mapping it's quite well studied how error-prone humans are/how hard it is to communicate the right subset of details, while VR research has demonstrated how well real-world representations work).

Regarding distractions, attention management is extremely important for AR, but has also been researched a lot. As long as we keep advertisers out of AR applications we'll be fine.

Not surprisingly, the military already uses it, and I doubt they'd give figher pilots AR helmets if a screen would be more efficient.