I have always had issues with not being able to lean forward in my shooting stance. I blame it on being overweight but it just seems so unnatural when I lean forward a little while shooting. Even when I think about it and lean forward when I start shooting I'm standing straight up again withing 4 or 5 shots.
Same for me. I'm also 6'4, so I have a high center of gravity + crappy balance. Leaning forward seems unnatural.