Any horse "can" do it, but if not done properly, you can build the wrong muscles and end up with a horse with less topline than before. If a horse has a hard time cantering from a stop or trotting from a reinback, then he is more likely to throw his head and hollow his back. If the rider in turn yanks the horse's head back down, then the horse will brace with the head and neck, which works the underside muscles, not the topline.
I'm glad it worked for you, but it's not something I would recommend to someone unless I know they are working with an instructor that can help them correct any problems that arrise. Just watch a (bad) amatuer reiner trying to canter, stop/slide, then back up. It's not too pretty, lol, and sadly not that uncommon.
There are many other ways to help build topline with less risk of failure. The more dramatic transitions are great for more advanced work or to further a horse's training, but it's not something I would personally recommend for a horse who's lacking in muscle. Baby steps are safer for horse and rider, and more apt to produce a better outcome and more lasting result.