However, I have another plan for next time. I will cast off above the foot and then pick up stitches again for the heel and toe. That way I can rip out a worn out foot and then once more pick up stitches and replace the foot. As one may tell, i am quite commited to experimentation and chagrinned to do two projects the same way.[/QUOTE]

Beautiful knitting. Design is very clever! You put a lot of work into these, and it shows.

I love a knitting challenge, too. What I have done with my heels and toes is to knit a strand of woolly nylon (sold for use in serger machines) along with the yarn. The stress points are then reinforced. It does not change the gauge. There's a slight color variation, like flecks of a tweed.

Your technique, to cut away a worn-out foot and knit on a new one, is often used to extend the hems and cuffs of children's sweaters.