I think Simon is objecting to the idea of taking a preparatory course before taking a technical class, on the theory that the technical class should teach you everything in one. It is my personal opinion that taking a preparatory class before either technical or cave classes is a very GOOD idea (and honestly, the Tec 40 isn't much different from that). Seeing the level of function that's required (or at least ought to be) at the technical level is, I think, very helpful. Getting your buoyancy, trim, propulsion, situational awareness and tolerance for task-loading bumped up before coping with deco bottles and midwater failures is completely worthwhile. I think most technical instructors would be VERY happy to be presented with students whose basics had already been polished. I know my cavern/Intro instructor was.