Yeah we've talked about that a bit. You can also confirm off of a j3 into d2 xx mb RLG, b3, j2, 1 crowbar or sweep for a hard KD.
This option is good for meterless stiuations (or if you don't want to spend the meter for whatever reason).
Last night in tournament I actually started off a match with d2 gun dash cancel d1 BGB into 2 unblockables to close out a life bar (it was casuals though... ).
Another thing you can do with this is do after the dash is cancel d1 or b1 into teeth for a setup if you don't think they'll techroll, which gives you a pretty nice midscreen setup. Useful after you've done this into flower and trained them a little already.
Just a few notes. This is, in fact, in the infamous guide project already lol.
Rather than doing the instant jump attack, we generally go for a crossup j2 or mb f3 in that setup. It produces the same unblockable situation and the crossup jump has the added bonus of reversing the opponents inputs if timed properly, while mb f3 eats wakeup attempts and smacks them back down into the teeth to be launched. Those 2 options cover most of the cast, with the only exceptions being teleporters like shazam, whom you
What a have to read it and jump back to catch them, and a few other specific things like Flash's flying uppercut going over mb f3 and generally tracking on the crossup (though he'll still get launched).
We also have a nice window for stuffing wakeups after raw (non-mb) crowbar into teeth into 21 or b13, depending on the character and the wakeup. b13 will produce a near unblockable and launch them into a loop for the same situation all over again. If the wakeup is slow enough, you can go into the infinite here as well.
This is cool too though. I like it for a high level yomi situation where you might make your opponent think you're doing some kinda DD-style crossup when you dash into them on the ground.