In the winter or cooler weather, I leave the new tire near the wood stove. Getting the old one off is the hardest part. Mounting should only be done with a good mounting lube. I use a bucket of Camel tire lube. Too slick and it will slip on the rim after mounted.
I agree with everything you just said about warming the tire, using Camel slippery gel lube (I have Cameal "Tru-FLate Tire Mount "STUF" Part No.12-095"), and the warning about the tire slipping on the rim.
Here is what I have found.
To remove the Rocket Roadster rear tire, I first remove the brake rotor (to allow the wheel to fit onto my plastic bucket with a thick towel draped over it for cushioning), then use a big "C" clamp to break the beads, then drill a hole in each sidewall, then "sawzall" cut all around both sidewalls. A cutoff wheel takes care of the bead wires (be careful the cutoff wheel doesn't touch the rim!)
Mounting the Roadster rear tire by hand is a little difficult, but if I use a slippery tire gel I can do it using regular tire irons and rim protectors. Before airing up the Roadster rear tire I remove all of the slippery gel, using "Ruglyde" watery tire mounting lube. I leave a thin film of the watery lube behind, then air up. i learned the need for this step when my tire rotated 180 degrees on the wheel in a 2 hour ride the next day (or it could have been 540 degrees, or even more, who knows?!) but it didn't lose any air, luckily. I wash it off now, to avoid that problem.
I find that getting the first side of the Roadster wheel inside the rear tire is more difficult than any other motorcycle I have changed tires on. On other bikes, a bit of lube and a push with the hand, or both hands, and the rim is inside the tire. Not so with the Rocket rear. The method I use is to put lots of gel on the tire and rim, place the tire on the ground, put the wheel on top, stand on the wheel and use a tire lever to persuade the rim inside the tire. This risks damaging the sealing surface of the tire bead, but I don't have a better idea.
I don't know why getting the first side of the rim into the tire on this bike is so hard...perhaps the rim outside diameter is deliberately oversize?
In contrast, the Roadster front tire remove/replace is a piece of cake. I use the regular watery "Ruglyde" tire mounting lube, hand levers and rim protectors to remove and install, with no problems, like a regular bike. I remove both rotors first so the wheel fits onto my bucket, and to make manipulating the tire levers easier.