I've tried that method, but prefer to put the lock around the frame. Yes, those locks are heavy, that's why I almost never ride with it and leave it locked to a bike rack by my office.
Tonight though I needed to make a stop so I took it with me. Big mistake. I should have just gone straight home like I always do. Got a flat, tried to fix it. It didn't work. Replaced the tube, pumped it up as hard as I could, it also went flat. No, I didn't check for glass coming through the tire as it was already dark out so I couldn't really see. I ended up on the long silver sag wagon.