You don't have to draw a straight line between the two injuries for it to be illustrative of the point. "Injuries beget injuries" means not only that you can hurt yourself compensating for one injury, but also that injuries(and especially 2nd and 3rd injuries like Cutler has already sustained) happen to players who (for whatever reason) are more prone to injuries. Correlation does not equal causation. It is absolutely unfair and ridiculous to only talk about his health since he broke his thumb but ignore what happened before that. Your theory is wrong and the only support is that if you pick out a guy with multiple injuries that will, by definition, "support" the idea that one injury somehow led to another. Injuries do not beget injuries. Tom Brady missed a whole season with an extremely damaging leg injury that has not led another injury. Drew Brees injured his shoulder early in his career and hasn't led to anything since. Payton Manning broke his neck, missed a season and has played 32 of 32 games since. Their injuries did not beget injuries because injuries do not beget injuries. That's some old wive's tale nonsense right there. If you were talking about running backs you would have something to talk about. If you were talking about a running QB who got himself hit, and thus injured by those hits, you'd have something to talk about.