You only get more power from higher octane if your engine is tuned for it. So if your engine is tuned for 98 octane the ECU can detect knock and still run on 95, just producing less power than it would on 98, and maybe even a bit less than it would if it was tuned for 95. But it won't produce more power if you put 101 octane in it.
So you could do that. Put 100+ octane in it, get it tuned for that, run octane booster when you go racing, and run 98 octane the rest of the time and rely on the ECU detuning the engine to run on it safely. That's how a lot of the upgraded ECU chips get the power increase they do. Instead of setting the tuning at the point that's best for 95 octane, they set it at the point that's best for 98 octane knowing that the sort of person who will rechip his engine is the sort of person who's going to be willing to always fill up with higher price higher octane fuel. And when they don't or can't the ECU will make sure the engine isn't destroyed.