Thanks for advice, Sky! And I am actually already doing leg stretches for him, as our chiro suggested - in fact, he really enjoys his hind legs (and also tail) being stretched, but is still somewhat fighting about the front legs. When I pick up a hind leg and start stretching it, he becomes very relaxed and happy about it, but starts showing attitude as soon as he feels I am going to pick or soak his hooves. Smart boy, heh.
As for his front feet, it is partially a soreness (the ongoing battle with thrush, frog and bar problems) and balance issue, but we're working on it. Last time I soaked his front feet he seemed to have become a bit more patient about the procedure. His reactions are not those of fear, though, that's a thing I'm quite sure about. He also leads with ropes around his legs quite easily. Altogether he is a smart and disciplined horse, but I feel that this problem we're speaking about here is going to be a good challenge for me and also Snickers.
I have come a long way, to surrender my shadow to the shadow of my horse.