Yeah your correct that the MR-SPG-DM sweep would come after you had already bought other stuff rather than just buying DM's straight so its an added bonus...
What i am thinking about is the best earn/burn rates for award flights and from what i have seen the offers at DM look pretty attractive. Not so much into hotel stays as i tend to stay in backpackers or hostels or couch surf with people unless work is paying for my travel.. And not even necessarily earn flights completely but top up towards flights or maybe be the different between a Y and J booking after mostly buying DM via regular 100% bouns offers... Only real prob is there are no star alliance carriers in Aust...
I am not really up with the earn and burn rates with Kris flyer which maybe better than DM but can't be combined with it i don't think so fragments up FF points/miles earna cross different ones...
So currently with Qantas at the mo i can earn 1 point per $1 with WWEDRCC and 1.5 points per $1 with ANZ Amex Plat... (strictly there are more points because shopping at WW you earn QF points on the $ spend over $30 (although i don't get much of this) and the card spend
With an Amex MR card i could get the equivalent of 0.6 DM miles per $1 cc spend...
Return flight Perth to LHR or LAX with QF is about 112,000 pts or double that in J with $800-1000 taxes and surcharges
Return flight Perth to LHR or LAX with DM *A carriers is 80,000 in Y or 120,000/110,000 in J with a possible stop over in another continental region plus $2-300 taxes and surcharges
It sort of looks like QF comes out ahead in raw terms of earn/burn for Y flights but for J would come down in favour of DM... Then again if you took the $800 cash difference in taxes and surcharges which would probably buy pretty close to what 60,000 DM up front the equation only becomes
(60,000) + 20,000 at 0.6 DM/$ = $34,000 of spend or (60,000) + 60,000 (for J) at 0.6 DM/$ = $100,000 of spend
vs
112,000 (at best earn rate of 1.5 points) = $75,000 spend???
The issue of no *A Australia
Perth to E/States = 36,000 QFF return (at best 1.5 earn rate) = $24,000 card spend
Perth - NZ - E/States = 25,000 DM return = $42,000 card spend
Not sure how DM's taxes and surcharges to NZ would compare to QF's probably fairly minimal within Australia...
So if most flights were going to be in Australia QF beats DM, if most was going to be international (which is what i do), especially if you wanted to fly J then DM even at a coughpy 0.6 conversion rate beats QF???