In reply to Ginger McGrath:
tie them together, clove hitch a krab to the main rope, clip rope back onto itself around the v-thread/whatever. make sure the tag line + knot is on the 'pull side'. off you go.
if youre strapped for krabs can also attach the rope back on itself with a loop (tied with a bowline or fig8 depending who you argue with).
as it goes, the screw gate jamming against the maillon is considered fully acceptable to the international canyoning commission (the most anal rope work people ive ever come across). they suggest clove hitching a largee HMS for the job.