Likewise. I posted my reply #12 above with the lubricant recommendations from DMT for their diamond stones---basically dry or using plain water. A few precautions also. It's worked for me for several years and I've never experimented with oil, WD40, or other lubricants.
They do get caked up and need to be cleaned frequently. That's why I started using WD-40 only as a cleaner. Then tried with WD-40 as a lube, and now experimenting with other oils diluted with turps. Medical grade turps doesn't bother me as much as other thinners. And I'm not talking about a heavy running coating of oil, just a light wiping.
Some other lubes seem to evaporate very quickly, I suppose they use alcohol as a thinner. I want something thin, not too oily, and slow to evaporate.
And Hank is right I have had the same routine for 15 years, recommended it to many members in workshops. Who says an old dog can't change his spots?