In my armed forces days(active duty MP/95B, now in 2013: 31B) we had to re-qual on a 9mmNATO range using both strong & weak hand training.
We also had to shoot the M9s from different positions; standing, prone, barricade, etc. It wasn't easy.
In my own firearm training with my own revolvers & pistols, I shoot with both hands to feel confident if I had a "wounded officer" event.
Some gun owners I know avoid doing it but I think it's a good skill to have or at least feel capable to protect yourself if the angle/position requires it.
Some top instructors like Massad Ayoob even shoot entire pistol matches weak handed(and win
).
Im not that good yet.
