This idea just came to mind while I was reponding to that "roll call" thread.

Starting today, I'm going to start tracking C class on flights that I usually take i) 72 hours prior ii) day of departure. That will give me a pretty good indication on which flight will give me no problems when the 72 hours window comes around.

I used to do this when I was a Gold/ExP with CP and acheived 100% on upgrades but stopped last year when we were able to upgrade at the time of booking.

Do you guys think this is an effective way of "predicting" C class or just a waste of time? I think it's worth the effort especially if we have to pay that much more for a shot at an upgrade. As we all know, airlines use historical data as part of their yield management system and I was thinking along the same line when I came up with this idea.