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The two studies contradict each other. If the NC study is accurate I'll take a few rear ends rather than t-bones.

There's nothing contradictory about it. They both claim that rear-end collisions increase when red light cameras go up. The only difference is in the authors' attitudes towards the cameras. As for the choice you present, we can reduce both without the red light cameras. You can have your cake and eat it too. I refer you to posts #6 and 48 in this thread.

The two studies contradict each other. If the NC study is accurate I'll take a few rear ends rather than t-bones.

The only way someone is going to get T-boned is if either:

A motorist enters the intersection at least a second after the light turns red
A motorist who had approached a red light proceeds to enter the intersection when his light turns green without noticing that another vehicle that had been in the intersection for at least a second.

The clearance time on traffic signals is typically two seconds, of which I allocated half to each motorist.

I would argue that optimal safety and traffic efficiency will be achieved if yellow times are fairly long, motorists proceed through intersections if they expect to beat the light, and if all drivers expect that motorists may misjudge the light slightly.

For optimal traffic flow, a waiting motorist should able to proceed safely as soon as the last cross-traffic vehicle that will go through has passed. If yellow light times are long, but motorists proceed through intersections they expect to reach before the red, these conditions may be optimized. A motorist who is going to stop at a light that has turned yellow will typically slow down well sooner than is strictly necessary. Doing so provides a generous safety margin in case traction is less than ideal, and also makes his intentions clear to waiting cross-traffic motorists. Sometimes motorists may misjudge the yellow might be a small fraction of a second, but so what? There's more than enough safety margin and redundancy to allow for that.

I would regard those who push yellow lights excessively as being discourteous, but there's a big difference in my mind between a courtesy violation and a safety one. Entering an intersection in such a fashion as to risk a collision with even an alert driver is a safety violation. Entering an intersection in such a way as to unfairly delay the flow of other motorists is a courtesy violation. I see no reason to assign even remotely similar punishments to the two actions.

Out of curiosity, if one of the cameras snaps a motorist entering an intersection after his light has turned red, but before the opposing signal has turned green, does it delay the opposing signal? If not, I'd say that's a clear sign the cameras are more about revenue than safety.