Nerve damage is definitely a component of this for sure. I’m glad yours didn’t cause you much trouble bro mine was fucked from the start I got a blood infection from the surgery. I’ve let it rest for a year and it’s doing a lot better so there’s hope.I've torn both of my biceps. My right was a third degree tear about 15 years ago (can't remember). My left was a 2nd degree tear about 5 years ago or so. Didn't have surgery on either (the one 15 years ago I was fat, only really see it when I leaned out). The 2nd degree I probably should have had surgery, but I was afraid of the downtime on my schedule. I actually tore it at the beginning of a game, had physio tape me up and finished the match, and then played a higher division match before getting it properly looked at....
No long term issues with either - strength is there, I can do chins just fine for example. If there's anything my right arm gets tired a bit before my left, but that's it.
Strange issues you are having. Maybe nerve damage? Maybe I was just lucky no nerves affected?
I wish I had more to suggest. I basically just rehabbed and moved on.