Nicklaus said in My Golden Lessons that before every Pro season he'd return to his instructor since age 9, Jack Grout, who would start him over as if he were a kid who had never held a club before.

Hogan advocated a 7i drill which is similar. Using just the 7i start with short chips, progress to short pitches then to full 7i swings. If at any point balance and accuracy is lost stop, back-up and solve the problem.

I did that as my practice drill to learn how to swing correctly and continue it as a warm-up. If playing without warming up, which I do most of the time I'll play tee-to-green with just my 7i for as many holes as it take to hit the targets I aim at with it. As Hogan would say, if you can't hit an easy to hit club why would you want to use anything else.

As for the question of handicap? What's more important, that number or improving skill. Personally I've never bothered with a handicap because I don't compete. Pros don't either because they play based on actual score and if they aren't competing every round is a practice round.

I think the better way to do handicap in competition in the modern era of courses with multiple tee boxes would be for the golfers to elect which tee they play off and then compete with others of similar skill level off that tee for scratch score. Sandbagging would be prevented by automatically moving a player back a tee when they finish in the top 10 in any sanctioned event. The better golfers playing off the tips could go out first, then each successive group on the closer tees. Pace of play would be faster that way I think.

There's little chance of USGA ever adopting such a system but nothing preventing a golfer from practicing and playing that way as they progress on the learning curve. It's also a good way to start after a layoff. Odds are you aren't going to be in top form with Driver so why not play a few rounds off the forward tees with irons off the tees to shake the rust off.