I wouldn't call that evolution; I'd call that having a poor angle to see the swipe tag.

Right...you can either be in a terrific position to see a swipe tag but miss a pulled foot or dropped ball or...just accept that the best umpires in the world are doing something that gives them more advantages than not. You don't have to call it evolution, even though it is a change for the better at such a competitive level.

My take on this (and on the "who has the second play in the infield?" issue) is that no position is perfect; whoever in "in charge" gets burned by a particular play and thinks "if only I was in this other position, I could have got that call right" so changes the mechanic and that's the way it stands until the next guy gets burned by the opposite play.

+1.