"" while there were significant advantages in maintainability, error recovery, and general robustness to having that driver code be in user space. ""
Naa!.. that was because your kernel (in kernel space) wasn't nearly as good as Linux... lol
Seriously, i think of a parallel, Virtual Machines... ummm... why don't run the all shebang in userspace ??
Almost impossible for many tasks & functions, right ??
A driver for a full blown GPGPU is the same. Things have changed a lot from earlier models... things can change dramatically in near future, you'll see... research like you mention is not only curious, it will be mandatory to do again.