Originally Posted by nhluhr
knowing that it takes at least a couple days for the trims to normalize to where they need to be, you should definitely reset the ECU when cleaning, especially if you plan to be getting tuned the next day, driving hard, track day, etc...
but for run of the mill driving around, i agree, no need to reset it.
That isn't nessessarily the opinion of a number of respected tuners in these forums. Most recommend not to reset if the changes you made are small. The car will make small adjustments within seconds of driving.