[stuartcr]

My guess is that we probably ended up using straight-edges, and right-angles in construction because of things like line-of-site measurements and plumb-bobs, to name a few. It would be awfully hard to have to deal with pi, and area measurements of curves in everyday life, but that's just me.

[Bikers4Bush]

Only because we didn't do it from the outset.

Were it part of our everyday life it would be no different than what we do now.