I have a couple thoughts on this subject.
you have not mentioned a safety
line (second
line) never go up on one line only; use the
jib or
spinnaker halyard as a safety.
if you have 2 primary
winches; get two of your mates to
winch together each sharing half the load.
if any of your halyard terminate in snap
shackles, don't use the
shackles, pass the line through the d ring on the chair and tie it off with a bowline.
West Marine has a recall on some of their bosun
chairs.