Joe, yes hanging a rug will sometimes be enough to cancel out slight problems, but you have to be careful how you hang it. If you hang it over something thin, like a 2x4, you are going to crease the backing. Also, if the rug has a fringe and you hang it the fringe could brown out because it stays wet too long. Let there be no doubt that if you are going to get shrinkage from over-wetting it will be immediate, and hanging the rug will probably not solve it.
As for the rug being just as wet with a water claw as regular cleaning, I disagree. Normally I do not get the backing wet on an area rug, or maybe just slightly.
az