Dave, congrats on the Bitz! You're right; they are the Cadillac of fletching tools. I tried a couple others, but was never happy with the "slop" in the adjustments... You'll never need another fletching jig the rest of your life now. I too started with a straight clamp, but am about to buy a helical clamp and start using that -- especially since I'm using a drop away this year.
As far as Trembow's dilemma, the one difference we've noticed so far is that I have only ever fletched with feathers, and he's using vanes... don't exactly know what difference that would make, but it's the only variable in the equation.
I may go throw up a thread in the Trad forum in the next couple days and ask their advice; after all, they're the masters!