Clay, HP doesn't necessarily transform into "speed".
A prop setup will pull a jet backwards easily, and will thrust the boat forward WITH CONTROL at much slower RPM's, even while pushing a heavier load.
Once you are up and running the jet pump will feed on the momentum of an already moving boat, like a tail-wind..... So being able to outrun a 20hp prop with a 30jet really doesn't indicate that there is less than a 10hp loss with the jet.