I think John's statement comes from the fact that a forward pattern valve body usually isn't a purpose-built valve body, but is instead a modified version of a factory type valve body. As a result, the line pressure you can use/achieve to apply the clutches is significantly less than what you achieve using a purpose-designed reverse patterned body. As a result of lower pressures, trans life would be shortened versus a reverse patterned build. I don't know if that holds true for Turbo Actions version, but that is the way I understood it from the version I was going to purchase from John before he talked me out of it.