The new-style raised arch (to the left, 92950) got introduced in 2009, and has been gradually replacing the old-style arch (to the right, 3455) across the board. However, after four years, not only haven't I run into a single set where it was structurally a necessity, but it also actually looks worse in all the sets I own. So I find myself constantly replacing new-style arches with old-style arches.
Just one of many examples: the wheel well of the VW Camper Van. The raised arch introduces a questionable corner on the back side, and an utterly hideous bump on the front side, both of which are completely uncalled for. Replace the new arch with an old-style one, and suddenly the curve is perfectly smooth on the back side all by itself, and on the front side you can easily make it smooth as well by putting that cheese slope onto a headlight brick with a 1×1 plate, thus effectively moving it ½ plate back.
Now, I understand that in the Tower Bridge, say, the old arch wouldn't work for the middle windows, as it is just a bit too low the way they are designed. However, here's the punchline: the new arch is a bit too high, introducing a gap that doesn't look right. In fact I only got rid of it by raising the middle windows by ½ plate, using some SNOT magic. That can hardly be the point.
So, has there been any kind of official statement explaining the redesign of this part? Or, failing that, do you own any sets that absolutely require the new-style arch for structural reasons?