I'm curious about this though, how do we know how much of an impact sprint will have on the design of the maps? We have yet to play any for that matter so that is mere speculation. Also it brings up the point will it actually artificially lengthen the game? The gameplay impression videos for the most part show a quick time to kill, and the shield no longer regenerates when sprinting. Your movement may have been increased but if the opponent is still firing at you won't you just die quickly anyways?
I'm not against sprint as to be honest if never felt like it really added nor took much away to Reach or Halo 4, just another ability we had implemented into the game. The games felt faster but not significantly where I felt it was a detriment to the game. Additionally I always preferred the speed of Halo CE to Halo 3, always felt a bit too slow.