A lot of people seem to think that slurry's primary purpose is to speed up cutting directly by abrading the edge itself. The use of slurry from every historical text I've ever read references its purpose to increase the rate at which the stone abrades (effectively lapping the stone with the slurry being pushed around by the tool you're honing) and consistently expose fresh abrasive particles. This applies to both naturals and synthetics. Exceptions I'm aware of being Jnat Nagura and of course coticules. The impression given is that in the majority of cases, the abrasion done by the slurry itself is insignificant compared to the abrasion done by the fixed particles because the slurry is simply pushed along before, rather than cutting the edge. Coticules seem to be an exception because their particles tend to only expose and cut with a very small part of their area when fixed to the stones surface. Also I recall some theorizing that the garnets in a coticule slurry tended to become wedged against surfaces of the stones fixed garnets due to their shape, causing the aggressive cutting of a slurried coticule.
So essentially. Yes, the vast majority of stones will cut faster used with slurry... not necessarily for the reasons you think, but they will. Will they perform similarly to your typical coticule? Not really. Yes, you can and people have dilu-thuri'ed and even dilu-norton8k'ed. It works in as much as it doesn't totally not work. But you could also prove that you can hone a razor start to finish on 0.1micron film... if your time really had so little value.