I did a bit of work offsiding on rig doing RC on Lakeway many...

I did a bit of work offsiding on rig doing RC on Lakeway many years ago, on a lot of holes for at least the first 10 meters, the rig would have to stop so we could open the cyclone and scrape a bit of mud out for the sample, the mud was so thick, sticky and heavy most of the sample was lost, blown out the collar and stuck to the inside of the hoses, and as you could imagine, scraping mud samples stuck to the inside of the cyclone would lead to contamination. We also had a booster set up to get the extra air pressure for the rather shallow holes, so I guess you are right, it can be done, but with the thick sticky mud near the surface its very problematic, especially if it continues for 80 meters!