no rush of course... It doesn't really add anything that can't be done with current trim/split tools. Just a nice touch that would add to Moi's freehanded approach... Have you seen the videos of the metaball modelers Teddy and ShapeShop (a.k.a. BlobShop) ? they have an interesting curve "eraser" that works just by scribbling a wavy line across the segment you want to erase. Somehow the program recognizes your intent as an eraser, not as a new curve. Of course it doesn't have the accuracy required by CAD. But it's interesting...

jonah