Scott,
I can tell by your posts that you're a good player and very knowledgeable about the game, but in this case I have to disagree with the specifics of your idea while agreeing with the general premise. I agree that you must be certain you pocket the 9 ball and I have always told younger players to concentrate twice as hard on pocketing the 9 than any other shot. This often means slowing down and I like that approach to an extent. I was watching a match at this year's SBE between Ryan McCreesh and Tony Robles and Ryan was on the hill with Tony one game back. Ryan's running out and comes up to the 9. It wasn't a hard shot by any means, but it wasn't a chippy either. Ryan takes a minute to walk over, get a drink of water, and towel off his cue. By the way his run was going, and the normal way that Ryan plays, I said to myself, "this is a mistake. He's going to dog this ball." Sure enough, dog city, and Robles comes back to win the match. In talking with McCreesh after the event, he seemed to agree that taking that long break before the 9 ball really hurt him because it broke his rhythm. I think that example is a common one for folks that play with a nice tempo and a steady rhythm. So, I believe that while you should concentrate more and slow down slightly on the 9 ball, taking too much time, or doing things that would tend to be out of your normal rhythm like getting a drink of water, may be more detrimental to the accuracy of your shot. But, if it works for you, cool. I just know I would get thrown out of rhythm.