I believe you are referring to Tomo vanguard 5'5" right? Reason why I mentioned Mr Buzz first short skate for Nathan and his high flying act then he went longer rails bigger with buzzsaw to 5150 surfs nowI think the reverse channels will add lift while in rail, but in the flats the tail will plane faster since there is little rocker. It does get bumpy in critical waves. Stretch showed me a clip of Eimeo in Teahupo testing the 5150 and it looked like a wild ride. It's designed for the high flyers where you do want lift in the tail rails to pop massive 8 foots airs like Nathan. I have a Tomo vanguard that has slight nose channels, and i think does add lift and help prevent pearling a little. But, if the board is designed to be 5'5" then I don't think preventing pearling is really a design priority, most of the design is to reduce drag and add maneuverability.