VTEC is actually very simple in its concept. Instead of one cam profile you have two, and you can switch between them. Any cam profile has a range of rpms where it is at peak efficiency. The ideal point for the VTEC switch is determined by the point at which the primary cam profile will make the same amount of power as the secondary cam profile. At this point, you engage the secondary cam profile and it picks up where the primary profile left off with no dip in power. The way you determine where your primary cam profile falls off and your secondary picks up is to do a dyno run with the VTEC point set very high so as to get enough data for the primary profile, then with the VTEC point set very low to get enough data for the secondary profile. Compare the charts, see where the lines meet, and there's your VTEC point. Deciding to arbitrarily lower the VTEC point by 1000 rpm or so will not really do anything for you. You do not need to change your VTEC point nor will you gain much power from doing so unless you have changed your cams and they need to be tuned.