I stumbled across this video.  What caught my attention was the pilot's precision.  The lines were straight and the nose didn't wander a bit.  You could tell the pilot had lots of Bucker time.   Then I read the title - it says Markus Ruesch!  That would be Albert's son?  He is listed as a member of the Swiss Aerobatic team.  If so, then that explains it.  See if you agree.

Update:

This article Pat Quinn wrote for The Vintage Aviator describes how Bruce Kemper and Albert Ruesch came to bring so many Jungmeisters to the USA. Markus Ruesch is mentioned as Albert's youngest son. - SB

Flight of the Angel.pdf