This does seem like case of the Percival Lowell Syndrome of seeing things that are not there
aka canals on Mars
the eye can play lots of tricks when looking at bright objects through the eyepiece /telescope combo
You say the seeeing was excelent then the planet goes behind a cloud
That you get such detail out of an 8" scope is in itself amazing,which by the way you do not mention any magnification (eyepieces ect)
I find your drawings dificult to fathom,but then again there will be some who will be able to decypher it better than me
Cheers