Flyers who travel exclusively on LUT fares probably wouldn't meet the MQD spend reqs. I haven't had the time to calculate my spend on DL in 2012 but I'll look at that this weekend to get an idea of what additional spend I'll need to qualify. Might just mean buying a few K+ fares rather than always purchasing the cheapest. That or cave into DL AMEX card and concentrate $25K spend on AMEX. For me, 95% of my travel is LUT fares because it's mostly personal. The few business trips I have require 21+ days advance purchase from our T&E policy so I'm not exactly booking expensive YBM fares anyway.