[member="Dax Fyre"]
The beauty of Force Drain is that you're really only draining someone's own Force energies, and can put that to whatever use you like, provided you're trained in such techniques. It's like Force Absorb: it's a means of gathering additional Force energy from an external source, like filling a jug with water. What you do with it afterwards depends on what Force techniques you're trained to use.
Now, it's not sufficient to reverse the effects of Force Light: think of the jug having a lid. No matter how much water you have to pour into the jug, you can't until the lid is taken off. The block on your sensitivity would have to be removed before the other person could make use of that energy you're giving them.
As for using it on a wounded ally, that's one of the ways that traditional Force Healing works: providing an injured person with additional Force energy, to supplement that being used to repair the wound. It wouldn't have a massive immediate effect - Force Healing is slow, and takes a lot of energy, but if you were to feed Force energy to a person in a healing trance, it would go quicker than if they were only drawing upon their own energies, for example. Also worth noting that such is a Light Side technique, so if you could use Drain Force, chances are, you can't use Force Healing. Go figure...
