I'm not sure that I agree, or maybe understand. If you mean the gain of a custom tune following the Penner Tune, then maybe/probably yes. But the Penner Tune is a tune and I found it made a very noticeable difference and not just at high rpm. The stock tune also greatly restricts at low RPM so a sudden twist of the wrist doesn't scare the crap out of the average rider. With a stock exhaust I see no need for a custom tune above and beyond the
@Penner Tune, which in my experience was a very noticeable and sizable gain. For what it's worth, most of my riding is in low gears on twisties, not long fast straights.
As I said, I may have misunderstood your point.