I guess so but I actually have metrics and quantifiable data to go by. What I can't do is determine a persons toleration/expectation of how that engine "drives". Your example of a 750 gaining 15hp will absolutely give up driveability. My threshold for moving to a bigger carb may even be based on when the boosters are activated and theres just no way to calm the fuel flow down when at a cruise RPM. A 500/4412 will actually cost 60-70hp on a 500hp capable build. Fact is I'd give up 20hp for better start/part throttle/tip in/cruise. Why? Because when you have all those other qualities-the car winds up faster anyways.
Years ago there was an amazing CarCraft article where the author put a car on the chassis dyno and tested I think 4 carbs from a 650-950? Not sure about that but.... The smallest carb made the least HP/TQ and the largest made the most, just like you would expect. Then he took the car to the strip and raced them while monitoring intake vacuum. Guess which carb went quickest? Yep the smallest one. Yes the MPH fell a little but it was very little IMO. Also the smallest carb created the most intake vacuum by a vast margin. I remember the take away and at the time I was dumbfounded. Those types of articles were few and far between that mirror what I've seen IRL. J.Rob