I happen to believe that any horse can go barefoot if given the time to heal from whatever damage the shoes have done. Shoes are a medieval invention, designed to keep horses hooves from falling apart when the castle was underseige and they were stuck in wet mushy stalls for weeks
I also think the Strasser trim isn't horrible. I think, though, it only works on horses who already have good barefoot feet. My horses have been trimmed by someone trained in the Strasser method for years, although she's changed it a little bit so that it's gentler. Their feet are great, even if I don't have them timmed for 6 months, they're fine.