DL MM in 13 years with no BIS:

DL Platinum credit card, $50k spend: 20k/yr.
DL Reserve credit card, $60k spend: 30k/yr.
Spouse's DL Reserve CC, $60K spend, gift miles to me, 30k/yr.

I'm also a member of Exclusive Resorts who offers 50k/yr. (little known to the FT community because of the high cost to join + annual membership), so for me that brings it down to 8 years. But of course I travel as well, otherwise why would MM mean anything to me? Will cross MM threshhold later this year.