Some customers are sheep, and will listen to the builder like he's a god or something. I'm an advocate of asking the builder questions about things like tube selection, assuming the customer has some rudimentary knowledge that is. For example, some builders use the same tubeset for almost every frame they build regardless of frame size and rider weight. If I were selecting a builder I'd like to understand the builders feelings on such matters before plunking down thousand(s) of dollars with them.