Why don't you give an example of a set? My understanding is that it loads the M/F version if present, else it loads the U version. Is there a set where this isn't the case (IE: it loads the U version even when there's a M/F version present)? If so, then name it and we can have a look at it.
the opposite is true, actually (first, the unisex textures are loaded, then, should these not exist, the gender specific ones)