it is illogical to YOU.
We have yet to hear from Airbus, Rolls, and DL whether the deal makes sense for them or not. If it happens, and I am making no promises that it will, they don't agree it is illogical.
The 346 has fuel burn that is about 20% worse than the 777-300ER. That is not a great disadvantage but there are larger fuel burn differences between older generation and newer generation aircraft, including early 737s vs the NG, and WN will operates a large fleet of older generation 737s, or DL's M80s vs M90s etc.
It is precisely because there is no market for used A340s that DL can set the price. Airbus can choose to reject an offer but why would they park usable planes which can be sold for any amount?
Rolls is not giving their services away. They are offering them at a reduced rate. DL already is a Rolls customer via the 890s.
And then there is the RFP for new aircraft which DL has out there... and DL execs have said they very much would like Airbus to move ahead with the 330neo as a replacement for the 767.
It is very possible that DL will use the 346s to push back a 747 replacement but go ahead with the 330neo if it is offered. DL has said their timeframe for replacing the first 747s and 767s comes in several years anyway and then only a few copies of both fleets will leave each year.
Not only does Airbus deny DL the possibility of acquiring new or used aircraft from Boeing (DL has supposedly been interested in used 773ERs as well) but they keep an Airbus model flying that would otherwise be parked.
I expect if this is true, we will hear within a couple months. DL has no pilot pay rates for the 346 so the likely reason nothing has been announced is because DALPA executives are aware of the order pending resolution of issues with DL including a pay rate for the 346.
With up to 19 Virgin 346s available in the next couple years, that is a lot of pilot growth that could take place if DL has the aircraft to grow its int'l system.