This is some serious shade tree mekaniking. We have half a dozen wrongs here. Driveshafts don't twist in two unless you apply a heck of a lot more torque than they were originally designed for, which means that either they added a compound low range gearbox to the drive train, or they replaced the driveshaft with some lightweight, high-performance model that wasn't up to the job. And if (when) it does twist in two, you don't patch it back together, you replace it. And if you do patch it back together, well, I guess wrenches are as good choice as any for patch material. And who carries a welding rig on the trail? I mean this was an emergency repair performed in the back of beyond, wasn't it? Not in some guy's shop where he has access to tools and, you know, parts. Some people are just demented, though I doubt anyone was injured by this particular deviation, except, well, maybe his girlfriend who had to sit and wait for this repair to be completed. Unless his truck is his girlfriend. Then she probably enjoyed the attention.