Dave,

Most of my fields are strips planted on the contour.  I planted some of my most curved ones this year and did not see any seed on the top behind the planter when I walked it.  Even on a couple really steep slopes where the planter had a very good dogleg to it from the tractor I did not see any problems.  I think even with the curvtine over the row it would not be a problem because it really does not pull things to the surface because of the design.  The tooth leaves the ground almost straight out not angled where it would pull things to the surface.