While you are fumbling with multiple clips, components, locations, D-rings, tying loops and whatnot, hopefully not dropping any of the separate components.
Rubbish. 1 bolt snap attached to 1 D-ring isnt exactly fumbling with multiple clips and connections is it. And what exactly is going to get dropped in this? There's nothing else in the way!
Any semi competent diver can unclip, prepare and launch a bag in 20-30 seconds at most.
If you want to invent pointless and unnecessary methods then thats fine but i cant see a use for it.
It can join things like bio-filters, dental gel, delayedaid and other things as solutions awaiting a problem.