Oil pressure vs lifter pump up

hi, few years ago, a fella with a hydraulic cam in a stock eliminator motor, tried a cheater lifter, a hyd lifter with out the guts, in essence a solid lifter.
NHRA decided to start checking for hyd lifters, so they were removed, and a set of speed pro, anti pump lifters were installed, the motor turned same RPM and MPH as the solid lifters did. speed pros. are ran at .004 lash. that indicates, the hyd lifter wasn't bleeding down at RPM. by the way, RPM was 7100 ,both cases. a solid cam is better, true.