I have seen this article a few years ago and had a chance to re-read it again. It is a classic. Explains Croker in a nutshell. I hope it gets a good work out with responses.
For me, my swing works with the two first points:
1- Make a conscious (Okay maybe not CONCIOUS but definitely moved) move to transfer your weight.
2- Don't "hit from the top." In other words, try to retain an acute angle between the clubshaft and your left arm as long as possible so you can "hit late."
This works for me.
This casting, as called by Leadbetter early in his teaching career or springing as Ballard calls it in his, never worker for me - ever. I get great power in sustaining the lag.
