I talked to the folks at Onestringer Caps last year and they suggested and had a video for using a hair dryer to heat up the caps for removal.
With the control you used, I see NO problem using a torch on medium and a quick warm up and removal. Slick!
I’ve been using hot melt to put in inserts (brown stuff) for many years and never had any carbons get brittle and some —I’ve shot for YEARS…so I can’t see using the torch to remove cap wrap would hurt carbon integrity—if using commonsense and not let get HOT —as you’ve suggested.
FWIW, I like to use GooGone and then wash with soap and water when I’m done removing old wraps.