Triangulation problem in plane cut

[Philo]

Sometimes when cutting a mesh, the cut plane gets a radial triangulation mesh. Worse, sometimes it gets outside the boundary, see attached image (done with MM bunny, first closed on bottom using an horizontal plane cut)

[RMS]

yea, I know about this one...not sure why it is happening yet. I have observed that often it will go away if you 'jiggle' the plane a bit...