I have raised this point about the surface before, myself. Maybe this reply should go in another thread, but since you asked for thoughts...
It should be fairly easy, at this point, to do a statistical analysis on injury occurrences across the league on the various surfaces.
First thing to look at. How do the Colts rank as far as injuries go? Seems like many to us, but every team has them, so look at the data.
Next, if the Colts do have many more injuries than other teams, is it conditioning (I'll guess not) or the playing surface? Do we have more injuries at home? Are visiting teams sustaining injuries when they play here? What are the types of injuries? How do they compare to teams that play on grass or other types of synthetic? Quite a few teams do play on grass so there should be some answers in the data. It might also be best to look at the types of injuries separately.
I'm no sports kinesiologist, but I'll make a guess that high rates of ACL injuries are due to too much tack in the surface. Sure, the players can make sharper cuts and don't fall on their butts, but that's no competitive advantage if the opposing team can also make those sharp cuts. Instead, it's a disadvantage when you play half your games on this high-grip surface and the injuries mount up from a foot that doesn't release to prevent knee torque when it should.
I have other thoughts regarding the surface and concussions which I'll save for another day.