Why Not Go Back to the Four-Day Format?
I agree that it would be very cool to have two AMA classes with MotoGP, and then also have a separate AMA weekend in September.
But in any case:
Who remembers when the Laguna events were four days long (Thurs-Sun)? For some reason (probably due to county permits, etc) they dropped the Thursday practice sessions a few years back. I bet if they put Thursday back on the schedule they could run all the AMA events alongside the world event, just like they used to. And hey - that was with six AMA classes (SBK, SSport, SStock, F/X, 250, ProThunder), plus WSBK practice, superpole, and TWO races! And it all fit in just fine.
Four days is better than three!
;-)