I always have to use two hands to complete this move. it's hard for me to move my thumb from "-" to the throw grenade button. so with my wii remote hand, i press the "-" button with my thumb, then with the nunchuk still in my left hand , I'll press the throw button with my left thumb. It works. My main grip with the Wii remote is that the buttons are to far spread out. I mean, what good is a tiny button that sits in your palm region? My hands aren't exactly small, I wonder how a young kid handles them?
The graphic glitches are everywhere, but I ignore them and play the game, which is pretty good.