Which part?
Where you said doubles need a larger wing because they lack ditchable weight? Or where you suggested ditching usable gas to solve an emergency?
Both are severely misguided.
The part that talks about dry suit failure.
Unless I missed something the OP was not talking about technical diving anywhere in the posts.
In any case there are many option and ditching the tank is one of them. What position it takes in the list of priorities is another question.
While calculating the weight of my wing i have to account for the weight of the gas as well as the buoyancy of my drysuit less ditchable weight. Simply because if my suit fails I have to be able to pull myself out with the wing and all the weight that I can ditch I obviously do not have to pull. Plus aome safety margin. I hope this is clear at this point
Given doubles have more weight that is not ditchable (at least that would be close to 6-8lbs I think in the form of bands and crossbar) you have to take this to the lift calculation. If you make a decision not to have any ditchable weight at all obviously tge requirements for the lift will be the same.
So if I have 10 lb of gas and my drysuit is 20 lb buoyant and no weight is ditchable i need to have at least 30 lb wing assuming my rig is balanced. If i have 10 lb ditchable I need 20 lb+ wing as i can get rid of 10 lbs in case of failure.
Now tell me how this is missguided.
Now when you say I will use redundant buoyancy... If your wing doesnot have enough lift its not your second redundant buoyancy device and you will have to have a liftbag as well. So that actually means that with too small of a wing lif you can only sustain one failure and if the wing is adequate you can sustain two.
The funniest conclusion that some people I see drew from the posts is it can only be one way either having the redundant buoyancy or ditching the bottle. Those are options and how you prioritize them is the choice the diver has to make.
And in case of DS failure your wing is in fact your backup buoyancy device.
Ugh thats a lot just to explain that the doubles give you less potential for ditchable weight