Problem surface for ExtendSrf

ExtendSrf.3dm (71.1 KB) contains an example where selecting a trimmed edge and entering a negative number extends the surface, entering a positive number shrinks the surface.

Even when extending the side edges of the untrimmed surface, the actual length that the surface can extend with _Type=Line is quite limited. This is true when either entering a number or dragging the edge.

Please add an option to _ExtendSrf to not shrink the underlying surface.

Thank you,

Using Rhino 6.0.16236.13271, 8/23/16

Hi Steve - I see that - thanks. For now, Untrim the surface and it seems to like that better.