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I would like to thank everyone who responded to this -- I learned
a few things from it, and I hope others did too.

To restate the scenario, it was an ocean wreck dive, where the diver
encountered a strong current as he ascended, found himself having to
hold on to the ascent line with both hands, and began to tire rapidly
to the point where he probably couldn't complete his decompression.

The answers to "What do you do now?" fell into two categories:

- Find some other way to stay on the line while attaching a jon line
  or clip to relieve the strain on your arms
    Various methods were suggested, most involving wrapping arms or legs
    or equipment around the line.  Another suggestion was to descend to a
    point where the current wasn't as strong, attach to the line there,
    and ascend again (figuring the new deco requirements left as an exercise
    for the reader :-).

- Let go of the line and drift for the remainder of the deco, expecting
  the boat to pick you up when you surface.
    This assumes that the boat can leave the site or that a chase boat
    is available, and the diver would have a lift bag or marker buoy
    and possibly an upline (one person did suggest a free-floating hang).
    Other suggestions also involved either the diver or boat crew cutting
    the anchor line and having divers drift with the boat (if no divers
    were still left on the bottom, or if a buoy could be attached to the
    anchor line).

The prevention suggestions:

- Do some research (weather reports, other divers, etc.) to find out
  what kind of current to expect at this site.
    This would, I'd imagine, be a first step leading to either a
    decision not to dive, or more preparations as listed below

- Attach a jon line or clip somewhere along the ascent, when the current
  first begins to pick up (this is also the suggestion I got when the
  story was related to me).  Also, use both to eliminate a single point
  of failure, or keep a grip on the line anyway.

- Make provisions in advance for drift decompression
    This included carrying an upline, marker buoy, and/or lift bag and
    having the boat be prepared to break away to follow/retrieve divers
    (using a buoy on the ascent line so the boat can return to the dive
    site)

- Have some sort of strain relief placed at deco stop depths on the ascent
  line in advance

- Carry all gas required for decompression - don't depend on staged or
  surface supplied gas.

And my personal favorite:
- "Stick to the caves"

--tab

-- 
Tracey Baker                                    tab@pa*.co*
    "I don't think safety is the main issue here...
                      You'd be stupid not to be safe."  - J. Comly

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