Hi Val, yup that's a bug although it's not new for v4 it's also present in v3 and earlier. The bug has to do with the process of extending the offset to make a new sharp point on it. The extension method used is a reflection method and when it makes a long reflected extension that's what makes the kind of crazy excess stuff. I've looked into it a little bit before and I'll take another look but it may be a fairly sensitive thing to mess with right near the end of the beta process so it might need to wait for a bit for a fix.

Thanks, - Michael