Hello William,
nice you are back!
I also cannot distinguish all my forms of D. venusta from D. "coccicaulis" (got it from Stefan some years ago, so far only vegetatively reproduced). But i have plants of D. venusta, that are quite different to D. "coccicaulis". Maybe the similar looking plants, that are around as D. venusta are also what PD called D. "coccicaulis" in his greenhouse in Munich? Who knows? And yes, there is no reference, that i know of, for Drosera coccicaulis other than the Articel from Robert Gibson. Anyway, i think it makes some sense to keep the name with this plants. I don't think, that a cultivar description can be of any further help in this matter, except for the validation of the name.
For me Drosera venusta represents one extreme of a large complex of plants, that definitely needs some work. I am sure, this will be done in the nearer future. So, let's wait what will happen. For me, D. venusta and D. natalensis are different enough to be their own species (although i would not say, that D. venusta is the best species). If anyone has some location plants of D. venusta/natalensis/dielsiana/aliciae, i would be very interested in them!
Some more offtopic. I can see more difference in D. admirabilis and D. cuneifolia than in many other species (size, stipules, styles.....). If adult plants are compared, they cannot be confused. Here is a picture i have taken, that compares D. cuneifolia and D. admirabilis. Even if you do not know the details you will see, that these plants are different. The D. admirabilis are not looking too good, as they werre repotted before the picture was taken.
http://www.utricularia.net/bilder/drosera/admirabilis_DROS69_018.jpg
Christian