In reply to PhilMW:
I've ascended bolts to get to the top of sport routes on my own, lots of times.
I would never use slings as you mention.
I put a knot in the rope and clipstick it to the first bolt, then clipstick all the ones I can reach. Jug up the free rope to top bolt, clip in hard to harness, clipstick again, until your at the top.
Its not free of risk, you need to understand what your doing, and be aware of the importance of the first bolt, and how the clip rotates on it to an upward pull. I add a tree on the ground if there is one present to back it up.
Once you get used to it, it only takes 5-10 mins to rig a route, and its not too hard to swap to an adjacent lower off.
Post edited at 23:54