Sounds interesting. I do the boring old cafetto + blind filter backflush routine on my silvia.
I have a thought/question that maybe someone can answer; I thought citric acid was used as a descaler in machines like the silvia (with no aluminium in the boiler). For backflushing a lot of people use the cafetto detergent stuff. This is where i show my lack of chemistry understanding...would citric acid work as a detergent for the coffee oils? Ive had a quick look around and I cant seem to find anywhere that says what the ingredients of the "cafetto espresso clean" are. But isnt there more to a detergent than acid?