Air Cooled Head Skimming

[Enternent]

I recall seeing a video where a guy had his air cooled head skimmed removing the round rims around each set of valves leaving a flat surface head. He used steel spacers allow for adjusting deck height to use his words. I have looked on the forum under Skimming for other members experience of this but couldn't see any posts. What experiences or pit falls have members came across following or considering getting a head skimmed?

[dave friday]

Ask on " the samba" ( google it)