I booked one of these yesterday. You can double-connect in the US on DL and the domestic legs book into full-fare F, so 200% MQM there. (You can also book on KL flight numbers for 200% RDM/40% MQD at the expense of 150% MQM on all flights.) Using Powertools, was able to book LHR-BOS-ATL-DCA-ATL-MSP-LHR for £1430 or so, which is good for just under 17K MQM.