Spice, I would say all of the c/sections that I supported have been positively affected, whether it be for the emotional support for both mum and dad that has been supplied, or the information I have been able to provide regarding procedures/protocols/what to expect etc. Sometimes because of the support I provide, the parents feel more confident to pursue changes in hospital protocol. For example, most of the mums that I have worked with have not been separated from their baby in post-op (whether I have been there or not). As a doula, I am not an advocate; I believe it is up to the parents to change policies and protocol, (Dads in the birthing room were unheard of until the mums en masse insisted on it; it didn't happen because of scientific research - see Michel Odent's recent articles) but I provide the information and options for them to decide if it's something they want to insist on. Medical practitioners are more likely to work with the couples wishes than listen to an outsider.
And most of the couples I have worked with also reported feeling much better emotionally about the whole experience.