Very interesting Nino .
 I haven't  heard (or read) about that before. (or maybe I forgot  )

It's something that I've been interested in for a while. I've seen some Youtube Vids where hobbyists are auto clearing EM playfields and there's more spray in the air than the playfield, plus, the gloss is too high. Looks GREAT on a DMD, but it  does not look right on SS or EMs. CPR clear their SS playfields with too much gloss as well. It looks ok, but it is not the factory finish. They should be more of a satin finish. I'm trying to replicate the satin finish on EMs that are closer to the original factory varnish.