That's valid, as that's seen as manipulating the hand. For example, to defend a rear choke attempt, people will grab the meat of the hand. Grabbing an individua

That's valid, as that's seen as manipulating the hand. For example, to defend a rear choke attempt, people will grab the meat of the hand. Grabbing an individual finger would not be okay. However, if you're going for another kind of lock, and the only control you have is the four fingers (no thumb, not applying pressure at base of hand), you're probably not going to succeed.