Well, I'm no teacher and the pump drill is all I know. I know there is more. The onliest reason I respond is because;
I have done the pump drill, practiced on the range and can hit shots with lag built into the swing. I have even had a couple of rounds o'goff with a lag swing. The problem is, without playing more than once or twice every couple of weeks, I can't trust meself to perform it reliably. I'll practice it and can do it on the range, but come game time, I just think about hittin the ball. I do believe some lag has worked its way into my swing thru practice, but not as much as I'd like.
When I play 2-3 times in a week, I feel comfortable with it.
What I mean to say is, it probably won't be an overnight deal. Be prepared to work on it.
Good luck to ya and happy golfing.