No, that is not what I'm saying. See Mr. Meyers's quote above.
I wouldn't choose to take a RV-8 or Harmon Rocket into a split-S at cruise speed and power on at any altitude. Clean aircraft like that can go past never exceed speed rapidly.
To be honest, I wouldn't do so in a Pitts, either, I'm not qualified. I don't recall ever doing a full split-S, just a very few partial ones when recovering from "unusual attitudes". Very few. My memory of them is overlayed by the loud voice in my head ( Or out loud, I'm not sure ) saying the four letter word for excrement, over & over. I make no claims of bravery. I might be a hero

But I was scared, I assure you.