ok im glad u took the time out to read the huge fucking thread i stole
1.) please get a video if u can
2.) ass to grass means u go past parallel where ur hams almost touch ur calves. i hope u r doing that.
3.) IMO u r getting the pain coz ur not doing ur stretches. Eric3237 has a bunch of excellent stretching articles and i encourage u to pm the big guy because although u have them, its not my place to distribute them.
so, get the articles, do the stretching and we'll see how it goes. if im correct, ur pain will be eliminated soon
best of luck