ive touched on the subject before that going to failure means the risk of injury increases:
"In a recent review Stone et al. (1998) noted that training to failure produces considerable fatigue. Fatigue increases the risk of injury, probably through changes in movement patterns. Additionally, the work of Nimmons et al. (1995) suggests that training to failure and beyond (e.g., forced reps) on a consistent basis can lead to overtraining."
ummm.....that's why you rest more if you're doing any type of HIT training, higher intesity=lower volume, more rest, more time to recover. If anyone is stupid enough to train using any of the accepted HIT protocols, like max-ot, BFT, DC or even pure HIT as perscribed by Arthur Jones and don't be mindfull of recovery then of course you're gong to overtrain and get hurt.
There are tons of studies that support HIT and tons of studies that denounce it, depends where you look and who did the studies. If we're talking practical experience than that's one thing but if we turn this into who can post more studies to back our side than this thread will become a train wreck. Not saying that's what you did I'd just hate to see it turn into that.