One thing that I always find a bit weird n these debates is the idea that mothers/parents should just 'suck up' sleep deprivation. Fine, if it's only happening to the adults, but if your baby is waking up every hour or whatever, chances are that he/she is not getting enough sleep either.
The effects of raised cortisol levels on babies left to cry is still very controversial, but afaik, the effects on babies and children who regularly do not get enough sleep is not at all controversial- it's been proven to be really, really bad for their development.
Given that, surely whatever method you use to get your child to get your child to go to sleep is better than that child not sleeping?
I'm not coming at this from any angle, btw, as I was lucky enough to have a good sleeper from about three months on, so I didn't have to employ CC or any other particular method. But my heart does go out to others who are being made to feel bad about using Cc, when that was most likely the best thing they could have done for their babies in a bad situation.