Kinda cool, but not very ethical at all.
2 Deer in 1 shot doesn't take much skill at all, you just need to be in the right place when you get the opportunity. And the opportunity of 2 deer lining up side by side while both are still in the proper position to hit the vitals is extremely unlikely to occur.
And pretty much a waste of harvesting a deer with an 8" hole blown through it.
Not trying to sound like a know-it-all, but I'm just saying.