It is not a "power" modification as much as a usability adjustment. The only measurable difference was that the throttle was smooth and progressive acting (like most bikes) and not so much like an on/off switch.
If you are asking how I measured as to where to adjust the TPS to, that is well covered in a how-to on svrider.org
Simply, you lift tank, plug in a "special dealer tool" (paperclip) into a connector and the digital dash turns to the onboard diagnostic tool. In this mode there is a line that stays steady until the FI kicks into it's acceleration state. When I checked mine, before adjustment, the line moved at ~3200 rpm. Instructions say to adjust down to about 1450 rpm, so it does not run so lean and jerky. Totally solved the problem I was having.
Bike also had a bad backfiring problem under decel that I had been thinking was exhaust leak (had been a problem) or that it was running too lean. Guess it was.