OP, I posted the same theory awhile ago in another thread. I say "theory" because I didn't bother actually testing it out with higher octane fuel. Anyway, someone said it was wrong because diesels have the chuggle too. I don't know if that's actually true.
How many tanks have been "chuggle free" for you now that you've starting using high octane? I'm wondering if it may come back over time like it seems to do with a tune.
2016 Colorado - 2WD Extended Cab LT V6 - Laser Blue - Shoreline Edition
Plasti-Dipped badges - Air dam delete - DRL switch mod - OPT7 LED low beams - Moroso catch can - Pedal Commander