I had about 300K in TWA lifetime miles in Dec 2000 when I really started to put on the miles and the pounds

. I'll be at 950K next week and at 1000K by say, March

. Mostly butt in seat+EXP bonus miles and about 100K in other promos.
My credit card bill varies from $1500 to $2500 a month, so that adds some.
I suppose if you were a plt or exp with some good bonuses, you could do it in about 3 years.
lala