If we are cleared to, say FL100 but SID includes waypoint restrictions with lower altitude, we stay in VNAV (given the restriction is in the FMC) but when cleared "Climb now FLXXX" many (me included) use V/S for the last 3000' or so as to avoid major thrust changes and stay in shallow climb while waiting for a clearance for higher altitude.
VNAV in our 757 does not reduce the V/S when aproaching the cleared level, but instead rockets upwards at 3500+fpm until about 800-1000' prior when alt acq engages, causing sometimes abrupt pitch changes.
Is a 500fpm climb the minimum required/allowed/expected when climbing or should the airplane climb as its performance allows and as soon as possible to assigned level?