Ok, this bug was introduced in one of the Fallout 3 patches and it is carried over to New Vegas as well.

Bug is that you always get 0% change to hit airborne grenades and dynamites in VATS mode. It was a true gun slinger tactic to quickly enter VATS mode just after enemy throws a grenade, shooting it thus causing it to explode and damage enemy.


Could this old bug finally be fixed for New Vegas?

I've been able to do it in New Vegas. I think it helps if you have a high perception+skill. It is indeed harder than it was in pre-patch FO3.

It's still possible to do this.. I mean the game recognizes it. I just did it out of vats, a power ganger was hucking dynamite at me, and somehow I managed to shoot it just as he released it and it blew up on him.