IMHO I don't think it is a good separation from a human point of view.
Actually, I suggested it because I thought it was better for humans (as well as computers). At least I know I personally would find it easier to use than any other split proposed so far. With the alphabetical scheme, if I want to look at the files for module foo, than now I know I would look for f/foo*. If I go to install a new module bar, I know where to put it: b/bar*. With any other split, it's anyone's guess as to where a module would end up -- everyone's brain lumps and splits differently. Whatever, I'm not trying to argue *too* strenously for a..z. karl