That Subaru video is horribly reminiscent of a friend's Triumph GT6, he and I spent a day trying to get a similarly long bolt out from the diff. That too goes through bushings and seizes, it was a horrible job even with 2 of us taking turns. I can't understand the guy's approach though, in light of your comments re using oxy acet, why the guy running a commercial garage is messing around for an hour trying to save 2 suspension bushes that have been on from new and are mostly knackered anyway. I'd just tell the customer "If it's all corroded in place, like this one appears to be, I'll probably need to burn out the bushes, it will cost X. If I'm lucky, happy days, you won't need them. OK?" Surely to God an hour's labour isn't worth a couple of bushes. In the UK plenty of mechanics reach for the gas axe before the spanners.