I see where you may heve been confused Chip. there are different things in what legend says:
> that this tea we see on the picture is not what it claimed, but that it is in fact yue guang bai. I think that from a picture only it would be difficult to be certain, although the looks of this tea is consistent with how yue guang bai looks, and not so consistent with usual looks of white teas.
> that yue guang bai is not a white tea, but sheng cha (so, pu er). that is correct considering the material & region. But, let's keep in mind that yue guang bai does not fall in usual categories : it is made of leaves that provide pu er (originally it seems from simao, camellia taliensis, but some is processed with other species in other regions); yet it is not processed as mao cha usually is (you can see the yue guang bai thread about that), in a way that would not really make it 100% a white tea either.
>that pu er falls into the hei cha category. this makes sense and is perfectly arguable, but this point is subject to different views among professionals, for different reasons. as you know, a tea can be categorized according to the cultivar/species, choice of leaves, to region, to processing(s), even habits in naming... some teas share criteria, so according to the criterion/criteria that is considered categorization can be discussed (and it is, a lot
(about the differences in definitions/categories with pu er, ginkoseto wrote an interesting post on her blog, it will give you an idea of issues in categorization vs evolution of market).