That's a good analogy Jim. I believe WGT keeps tweaking the VEM to where the members need to keep adjusting their game. This keeps anyone from getting use to the same game play in Ready-Go's, or multi-player match play for credits. It's always going to remain this way IMO until a version 2.0 download comes out, or the game goes to disc.
Like Jim stated above, we have to keep adjusting to our game play on a weekly basis. It almost seems like WGT is doing background maintenance and this is some what screwing-up the game. Last week my game was all screwy across the board, I cleared my caches, and the game has played flawless for me ever since. That's BETA for you fellas!