Pandora's Pencil Box: are there limits to artists' intellectual property defenses?

By now some of you have probably heard of Greg Paul's situation on the Dinosaur Mailing List. His posts there have generated a lot of controversy, but without taking any particular side here, in short the issue is about the very real problem of paleoart plagiarism, namely of those scammers who blatantly copy Greg Paul's specific works verbatim for paid projects, often also underbidding him and making it that much harder to earn a living from paleo-art. So with good reason, he's threatening to sue the plagiarizers (and possibly museums or publishers who hire them for a pittance instead of going to Greg Paul and paying a fair price for the real "Greg Paul look").

However, he's also suggested that others not even use similar poses in their skeletal restorations. The classic "Greg Paul pose" with the left foot pushing off, is apparently something he wants to make into an exclusive brand. Unfortunately this is already a very common pose among skeletal artists and there are only so many ways you can pose a profile skeletal and still have it be accurate. Copyrighting poses raises a specter of slippery slopes where if every artist copyrighted different poses, eventually it would be impossible to draw an accurate skeletal without being sued. Instead of stopping intellectual property theft, this could stifle legitimate creativity. Skeletals of different artists look noticeably different, even when the poses are the same, i.e., a Scott Hartman skeletal looks different from a Greg Paul skeletal.

Now admittedly there are others on ArtEvolved whose knowledge of these issues is far better than mine, so what do you all think about this?  I understand copyrighting poses from a particular live scene of dinosaurs - after all, to copy those, you have to replicate not just the pose but the exact angle too. But with skeletal drawings the default angle is always a side view, and there are not very many ways to accurately pose is given our current knowledge of paleontology. Can poses really be copyrighted for skeletals? Should they be? Or is this a Pandora's Box of legal disaster for paleo-artists?