I've posted on here a lot over the last year so wanted to say thank you because (touch wood) my ds is sleeping through from 730-630.
I used gradual retreat, a lot of will power and tears and most importantly my husband (for the last stage when I was about to break).
I think the trick for us was a good routine, time off work, stopping breast feeding, perseverance and feeling that ds could do it with help. but mainly it was the decision that o wasn't going to give up until my ds was happy in his cot on his own amd could get himself back to sleep- all without milk.
It isn't perfect. We leave him with a few dummies so he doesn't need us for that and for some reason he still gets very upset in the morning until we pick him up.
I can barely believe it has finally happened- good luck to everyone still struggling (I'm sure I'll be back with you when teeth, holidays and illness mess it all up!)