If/when DL comes through with u/g on award tix and AS flights, I would call both or either a significant net positive.

I agree that the SWUs need to be improved. Maybe not LUTs, but rather something along the lines of 2 SWUs useable for one-way u/gs on international HQKs. Just thinking out loud. Even if a DM chose the maximum SWU choices and exhausted their full SWU arsenal, we are still only talking about upgrading two and a half round trips while ensuring they don't buy in the bottom three fare classes for those flights. Maybe some cost for DL, but I suspect it would also buy an even greater amount of loyalty and provide a carrot for many fliers currently using a number of carriers to concentrate their travel on DL to reach for PM or DM.