In reply to stevomcd:
> 1. Thread the rope through the two maillons attaching the chain to the bolts and lower off those. Works, but the friction is horrendous.
Works I guess.....
> 2. Thread a sling through the maillons, put a screwgate on it, then lower off the screwgate. Recover the sling and krab either from the top (access is easy) or by traversing across from the top of your next route.
Well, if it works........
> 3. Live dangerously and just thread the rope behind the chain, lowering off the chain.
God no! As you point out, this removes the entire backup of having two bolts.
I would personally abb/lower off the maillion on the lower of the two bolts. You've got the chain backing it up to the other bolt, in case it fails, and the friction will be tons less than using both maillions. Thats just my opinion though.
AJM