Sorry about that! Yes the mapping is still the same and the points on the map being used get adjusted (slightly) by changes sensed by the correction and control sensors. A reset will not hurt anything, but after only a change of exhaust and an ECM reset, the map points will re-converge to the same place as if a reset was not performed at all.

A reset should be performed if a new ECM is installed or if any sensors have been replaced. A new sensor will behave a little differently than, for example, an oxygen sensor that has 100,000 miles of carbon build up on it. Or if a sensor has been slowly failing over time, this may cause the mapping to diverge to a set of map points that will be quite different from where a fresh sensor will point to. Resetting the ECM will put it in a known and tested "safe" location; not resetting when replacing sensors could result in a rough running bike until enough cycles have been run for the corrections to fix things.

A great example for all of this is how the engine uses the barometric pressure sensor. Oxygen content in the air that the engine breathes is very different at sea level and at high altitudes. These differences affect air-fuel ratio (AFR) and, in turn, that affects performance, fuel economy, and emissions. The baro sensor causes mapping corrections that maintain the right AFR wherever in the world you may be riding.