After 13 weeks of recovery, I detached my sub-scap muscle / tendon from the prosthetic. I did this by increasing the weight of a particular and recommended exercise too much.
So now, after a successful repair, I am back at "square one" with 4 weeks in the sling and 4 months of rehab.
But the real reason for this update (especially because it is posted in the "Pedal Steel" section) is to address technique changes related to the original shoulder repair. Hopefully others will be able to benchmark their comparative experience given a similar shoulder replacement.
During and after the first 4 weeks in the sling, practicing and playing was not too difficult. Fatigue in the left arm (bar hand arm) set in rather quickly though. Initially, I could play / practice for 10 to 20 minutes... and that was it for the day. As the recovery progressed, say by the end of the 8th week, I could play / practice for an hour... but I was very tired after that. By week 13, no fatigue. I played at the RISGA Steel Jam for 3 hours - no problem.
At first, bar movements were a little shaky, inaccurate and abrupt. These issues straightened themselves out quickly. Muscle memory returned and intonation issues improved. Right hand technique and pedal / lever coordination suffered a little because of the reduction of seat time, initially.
Toward the end of the 13 week recovery period, I did notice an improvement in the quality of playing over and above from where I was before the surgery. There was a sense of a little more confidence and fluidity in my playing. It is hard to describe but I have experienced this during other instances when I have put down an instrument for a while and have come back to it. Curious.
During the recovery period I had time to concentrate on more Music Theory. Bryan Clark's (Modern Music Masters) classes were / are a big help and taking time to dive into particular topics on YT proved helpful. So there is another silver lining. So, I am now back to looking for silver linings in my current situation!

More updates to Follow.
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Hey You Kids! Get Off My Lawn!
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