IF I was bowling only 1 or 2 leagues in the same house I might suscribe to your theory - HOWEVER - I bowl 1 or 2 scratch tournaments a month in various cities, counties, states, etc., along with my 1 Friday morning scratch league. I see good wood lanes, bad wood lanes, good synthetic, bad synthetic, various house shots, various sport shots, oil types,  etc. It is unrealistic to expect to be competitive with a limited 3 or 4 ball arsenal. Sorry - but it ain't gonna happen. Not in this day and age. If you're bowling on all those conditions, you're going to need at a minimum 7 or 8 balls plus a spare ball. A more complete arsenal would be around 12 balls with a spare ball. If you're going to carry an arsenal to tournaments, you need to use the balls from time to time to stay current with how they stack up against each other on various conditions. As you can tell from my original post, my home center can throw surprises at you from time to time. I always take 5 balls plus a spare ball into the home center for league, and have an 'emergency' 2 ball tote in the truck with a dry ball and a flood ball (since those are rarely needed). Since I have a tourney tomorrow in the home center, I figured I'd leave the 'dry' ball at home and stock up on the more useful stuff just to practice a couple after league and 'fine tune' the arsenal. Soooo, while I too wish we were bowling in simpler times, sadly we are not. If you're gonna play the tournament game and hope to cash from time to time, you need to be prepared.

Yep - When I practice I like to throw a game or three with a rubber or plastic spare ball. You can still shoot 580 to 650 reliably playing out in the track area, and even the occasional big set. I enjoy those games immensely, but you're not going to make much money doing it on a regular basis.