An interesting side effect of deciding P1 really isn't worth it, is that upgrades suddenly become more valuable. Traditionally, I've always booked flex. Recently, in the absence of DSC promotions, I did the sums and figured that I couldn't be sure of achieving P1 and for the limited benefits to a domestic flier, I was better off to book cheapest flight every time. Only downside is that points upgrading becomes expensive. Those 1:10 upgrades become correspondingly more valuable!
