Don't believe everything you read!
I KNOW how to hit AmericanTwist serves. The first guy I ever hit with at GoldenGatePark had the best twist serve YOU"VE ever seen. ArtLarsen.
My twists bounce about eye heights to a 6' tall player. My slices around bellybutton high, as does my flats. My topslice second serves bounce about armpit high.