imo, stretching has a lot to do with DOMS. I've been stretching a lot the past few months and DOMS has decreased a lot, yet i know that im seeing results from my training. Take calves for example, i thrash them every time i train them to the point where after a set they are absolutely killing me, yet i stretch my calves HEAPS, in between sets and after, and the next day they are only a little sore, where as before they would be sore for days on end.