Once you can hit balls striaght with a 90 deg. shoulder turn, can you increase the shoulder turn to 100 deg. + and still have great golf shots? Thanks, Ted
Short answer, Yes. However most folks have a hell of a time staying "on-plane" just back to where their front arm is horizontal (90 degrees). (NOTE: When your front arm is horizontal your arm should be parallel to the Extended Target Line. If your arm is pointing more behind you than that you're under the correct swing. If your arm is pointing outside that line your above the correct swing plane. That's why we use that horizontal position as a reference.
How far you turn past the lead arm being horizontal "without reducing accuracy and consistency" depends on the musculature and flexibility of the individual. Yes, most people can have their arm go 10 to 30 degrees past horizontal and add some power. A flexible few can go even farther.
I'd recommend your "normal" full swing shot go to horizontal. That's what I do for maximum consistency and accuracy. My maximum distance backswing with a specific club is probably 10 to 30 degrees past horizontal. That maximum distance position is used when I'm between clubs and need to jump on it a little bit to get it there. (I don't try to swing at the ball harder I just try to make a bigger shoulder turn.)
Now when I'm playing a scramble and my teammates are already in the fairway I certainly try for a maximum shoulder turn which for me is a goal of being 45 degrees past horizontal but since I'm not very flexible that pretty much as far as I can go and I can't always get there. Obviously when I do that I'm not as accurate or consistent as normal (because I'm trying to kill it) but it can result in some fun maximum distance shots.
THE FACT IS THAT MOST PEOPLE GET IN TROUBLE AT THE TOP OF THEIR BACKSWINGS. It's very common for people "to cheat" to try to get a little extra length in their backswings. They often let their front wrist collapse (back of hand bending towards top of forearm) and that get's them off plane. Sometimes they over rotate their lower body getting "extra" muscles into the swing that can throw off their timing. Others "lift" their arms instead of turning the shoulders completely. A little lift is okay but the danger is that the arms tense up and you start swinging with the arms.
Bottomline line: Longer backswings give your very little in power gain and often come with significant reductions in consistency and accuracy. Watch the PGA Tour and you'll see a definite trend towards much more compact backswings.
How long your "ideal" backswing length that balances power, accuracy and consistency should be depends on the individual. For most golfers especially higher handicappers limiting the front arm to going horizontal will be the best balance. With some practice many people can certainly go a bit farther.
"....They often let their front wrist collapse (back of hand bending towards top of forearm) and that get's them off plane."
Just realized the other day that I do this ( wrist collapse ) Oh well, we're not pros here....knowing that I do this, allows me now to work on that item.