I think the caution with regard to the tubes has to do with them "stretching/expanding" over time in the tire . When you put on a new tire and use the old tube there may be a problem with the "oversized tube ?"
Regarding patching a tube I can relay an experience I had with my new set of tires and tubes that I put on before my first flight in the AC. During installing the wheel pant I ran a drill bit thought the tire into the tube . Yep I should have known better and taken the tire off before drilling !
Now that the tube is flat I thought it would be no big deal to patch the tube as I had done many auto tube repairs as a teenager working in a service station . I cleaned and ruffed up the tube , applied the cement and put on the patch and let it cure . No way in Hell could that patch come off that new tube ! During my first few taxi tests , I took the runway and ran up the power and about 50 feet into the run the AC pulled to the right and went right wing low . HOLY BATMAN ! How could I have a flat tire ? Sure enough it was flat and the nice EAA folks at Brown Field towed me off and I pulled the tire only to find that tire patch had come off !
I can just imagine how much of a pain it would have been to control the AC at TO or landing speeds with a flat ! My flat probably took place at about 15mph . I no longer patch AC tubes .
RB
POW !