Got super duper high the other night and went alien on my friends double end bag for an hour straight. No shit, it was like I was in the fucking matrix or something. You're definitely correct, it opens doors to creativity and movement I cannot reach whilst sober. I felt like a boxing genius, my speed, fluidity, and creativity were well above normal, and it was just fun to sweat my ass off, didn't feel like work at all.
Edit: It's funny you should make this thread, I was telling my friend the same thing, and I'm seriously thinking about videoing a session of smoke and bag work, and putting it on sherdog to prove it.