Variable Fillet/blend/chamfer Srf invalid: Why?

(Rhino 6.5)
Why does the command "Variable Fillet / blend / chamfer Srf with a patch surface not work? (Image on the right). If the surface is not a “Patch”, the command works (image on the left).
(instead, the Fillet Srf command works in both examples).
Fillet Srf Variable not valid.3dm (406.9 KB)


Hello - it has nothing to do with the patch, it has to do with the surface intersection being incomplete. Please see Help VariableFilletSrf.


Thanks Pascal, very kind :wink: