Thanks Kettlewell and Thinwater for the discussion of the pantomime Tinkerbelle idea.
I too had thought of this idea, much as Kettlewell describes, then discounted it, much as Thinwater describes.
But it does strike me as perhaps having a more limited but useful application on a well-crewed
boat, in specialised conditions where a tricky job has to be done on the bow - perhaps to do with tending to (say, chafing problems) with a parachute, or even bottom-anchoring operations, in open waters, in a survival context.*
Once again,
as a backup to the usual clipping on, but in extreme situations - say the
jacklines have been compromised, or there's the need to repeatedly switch attachment points, and particularly where time is of the essence.
I visualise a reliable other person at the
winch, acting as a minder and line
tender, to keep the
halyard "on belay", but not taking any weight unless asked to.
If the pulpit is undamaged and of offshore-suitable robustness, my idea would be, on reaching the bow, to unclip, pass the
halyard through it from above and in front, then reattach to the harness -- given that the risk in this situation is of being swept aft.
Halyards on a cruising boat should be extra long for use winching MoBs back on board, in an ideal world, so this would give some
scope for coming aft without unclipping.
*I think the idea is positively dangerous when there's any prospect of
capsize - at least up until the halyard is re-led through a low lead point - which is why I limit my interest to situations where the boat is held rigorously head-on to the seas.
A similar idea could also be considered when working off the stern, using a main halyard or topping
lift - say setting up an
emergency steering system, or repairing a vane
gear, provided once again that there was no propect of
capsize.
It makes it a doddle to get the person back on board if they do slip in. (which even a conventional harness cannot prevent, in this situation). However at the stern it would
work best with a harness allowing for rear attachment, below the nape of the neck.