Very interesting BBB.
I swear, my body conspires against me in my sleep. I've had issues with this arm years ago (ulnar neuropathy, elbow tendinitis). Whenever there is any irritation, I wake up in a worse state than I went to bed. I have woken up with my hand, forearm, and upper arm maximally flexed. I also woke up with my traps contracted. !!!
Last night, I went to sleep with a light fleece jacket on...woke up and it was on the floor. I do always use a down comforter though. But I think I need to put a sleeve only on the arm, because I get too hot with a long-sleeved top.
Shall try some of your AR-R. I have never heard of, or seen, ibuprofen gel.
I skipped a couple days of training last week thinking that grip overuse was contributing. But during that time, it actually got worse from playing piano. (Perform/work on weekends.) I tried a neoprene wrap on wrist while playing, but don't think it helped that much.