Jwat,
I was dinking around with a club earlier and thought of your experiences with tugging and taking the club back further than 3/4's. I then thought of ekennedy's suggestion that tension causes tugging.
I took a slow-mo swing and stopped as soon as I began to feel a pull on the outside of my left delt, kind of a sticking point. At this point I had made slightly more than three quarters of a back swing.
I slowly lowered the club until the tension on the outside of the left delt dissipated, then gunned it with my right arm. Hmmm, I thought. I have since come up with a few different options for we tuggers.
1) Stop the backswing short of the sticking point. I think this is what JB Holmes does, possibly because he has a problem with tugging/horizontal handpath.
2) Extend the backswing beyond the sticking point, and allow for more of a free fall to begin the downswing, falling just past the sticking point, at which time the club is whooshed.
3) Increase the flexibility of your shoulder complex, take all the backswing you can, and gun it from the very beginning of the downswing.