SOLVED - I think…
Well, I feel a bit foolish, but the outside shower valves were open. They didn’t feel like it, but they were. Turning right (righty, tighty) there was considerable resistance, so I assumed (ass-u-ME) they were closed. Not the case at all he said blushingly.
Dang I feel foolish! I believe a good test coming out of winterization, is to try and turn the shower valves on. If you hit a hard stop, they are on. A slight wiggle when turning right just may indicate an open valve.
The temps went up to 96° before I turned the water off.
The good news is the Truma is decalcified. Bad news is I am embarrassed.🙈