Same behavior in ZB with buildup brush.
An interesting fact is that all your "problematic" surface tools (except buildup tool) have this buildup option (in options bar).
Although not enabled it builds up a bit at the end.
I have a question about the viewport.
Why is it that in newer versions of 3DC "left is right" and "right is left" whereas in older versions "left is left" and "right is right"?
this drives me nuts.