He definitely seemed to be running the black key, not the red. Also, he was too heavy on the throttle initially, you really need to roll into it or you waste a lot of time spinning. Traction also greatly depends on the tires being run, many Hellcats come with all-season Pirelli's which are decent in cold weather to keep you on the road, but terrible when trying to put any real power down.
All that being said, I've had a 2016 Challenger Hellcat as my daily driver for over a year, so I'm very used to the power and what it's capable of. I've decided to give my spare car (a 14 Focus SE) to my daughter for use at college, so I started shopping for a replacement. I went to a Hyundai dealer last night to test drive a few Elantras, and they had a used Stinger GT AWD to my surprise, so I asked to take it out. I couldn't believe how much fun that thing was to drive. While the Hellcat is rated for a much quicker 0-60, the reality is, even with good summer performance tires, I still struggle to put the power to the ground, so the Stinger with AWD wasn't far off in terms of seat-of-the-pants acceleration, which really surprised me. It sounded really nice as well, not quite the V8 + supercharger whine of the Hellcat, but pretty good. Hence why I'm now on the Stinger forum researching and trying to justify to myself spending a lot more than I had intended for this spare vehicle!