I want to say that their are really three main golf swings that have been successful over the years. 'one plane', 'hybrid', 'two-plane'. DO NOT mix and match advice for one swing model into a different model. For example do not have a two-plane down swing with a one plane backswing that will likely give terrible results.
Like I have said previously RS1 or RS 1.0 is a 'one plane' swing model, it has specific sequences for that swing. RST or RS Tour is a 'hybrid' swing model, it has different specific swing sequences from the RS1. If you are a two-plane swinger that doesn't want to completely overhaul their swing neither model is a good fit for you.
If you are wanting to over haul one thing in your golf swing it is 100 reps to start to get the feel and 3000-5000 reps to have it in muscle memory without thinking about it, that is a lot of CORRECT reps to get something fixed in your golf swing, you just have to put in the time and practice in doing correct movements, commit to making the change, there is not a quick fix in golf to a great golf swing, PGA Tour pros didn't get their by being lazy in practice time.
First thing that is just gonna take a lot of reps and practice to remove from my swing is getting to fast from the top with my upper body, when I try to hit one hard my shoulders start working to hard from the top of the backswing causing a cast move. Shoulders just have to stay passive in the first move into the down swing, when I do that I generate a ton more lag and better release freedom getting my hand back out in front of my body.
The next issue is pulling an Annika with my head releasing before impact, she is probably the only person that I know that can move their head and get good contact at the same time. Normally i top balls or hit them a little thin when I 'cheat' and look up a little early. I placed a ball out in front of the target ball I was hitting making sure to keep the 2nd ball in my peripheral vision well past impact allow my arms and shoulders to swing around my head then pull me up and out of the shot.
Both things that are swing flaws in my swing currently are just gonna take time to remove, some days I get them perfectly and have my A game that day other days it is really bad and have my D game for that day. This won't fix in a single week or even a couple weeks it's going to take doing drills and practice of correct reps. 3000 - 5000 of each point to really get both of them a firm hold in my swing.
This stuff is most noticable in a fairway metal off the deck and longer irons, short irons and driver allow a little room for error and get away with things, so when I practice you see my hit a ton of my 4 metals off the deck on the practice tee / range to get a feel and even a 3 iron and hybrid / rescue club it is easier to feel the sequence with longer clubs, wedges normally you don't have weight shift back and through most time weight is left mostly on the front leg like a stack and tilt type swing.
RoverRick, I was reading your response and noticed you said two things that the RST swing model is big on efficiency and preventing injury over the long term.
The RST talks a ton about preventing injury and what types of injury can be caused by improper posture and positions in the swing. Back pain, lead hip injury, lead leg knee injury are the most common they talk about, but they also talk a little about how to prevent 'golfers elbow'.
I mentioned a likely cause and drill to fix thin shots with this swing model above in my experiences so far, not sure if that is the reason or if the left shoulder is working up and out through impact, the left shoulder should feel low and level at impact in the RST swing.