I don't actually subscribe to that discount theory. I think the discount actually draws people TO those party nights, especially with tickets already as high as they are.
We were at a sold out party on a 12/16 (a Tuesday) in 08. I later heard the prior Tuesday (the 9th) was also sold out. That Thursday we also went (the 18th) but it wasn't sold out. I didn't understand, but finally put it all together when someone here pointed out that the 9th and 16th were the discount nights.
Didn't matter in 09 when every party that last week sold out.
Last year we were there the 14th and 16th but the weather drove the crowds. Tuesday night it dipped into the 20's keeping the crowds at bay. Thursday the 16th was the most packed (and sold out) I've ever seen.
Another point....... when people say avoid the weekend, I agree, but only with Friday. I think Sunday could actually be preferable to the mid-week nights. Fridays sell out because of the locals who come out. Sunday that's not an issue as they go back to work the next morning.
Soooo.......
1) Always avoid Fridays if you can.
2) Early to mid-November is best.
3) Avoid Veteran's Day
4) Avoid the very first party after the Thanksgiving break.
4) ANY date in December can sell out
5) If going in December, the earlier the better.
6) Once you buy your tickets, stop thinking about it. Unless you're going in November, don't expect a small crowd.
That leaves .......... what?............... 2 or 3 parties with the potential for a small crowd?

I'm pretty sure the Disney bean counters planned it that way.
