The discussion of hauling in an anchor reminded me of something I have
been thinking of for a couple of years, continuous furling of a normal
mainsail without replacing the main or the boom. This means that
small modifications could be made to a main so it could be raised any
amount and pulled from fully raised to any extent. Current reefing
systems are mostly incremental using one to three reefing levels (reef
points). There are in-mast furlers which I do not like because they
can fail with the main up and because they do not allow for battens
and there are in-boom furlers that require a special boom. What I
want to develop is a simple add-on to a boom allowing any main to be
continuously reefed.
Pulling down on the luff (the part of the sail against the mast) is
not too complex but the leech side (the outer edge of the sail) also
needs to be pulled down and the point from which it is pulled varies
as the sail is pulled down to the boom. One can imagine an attachment
to the luff puller to allow this. Both of these would require some
sort of reinforcing on the luff and leech to allow it to be gripped by
the puller.
However, reefing systems need to also grip the sail along its bottom
edge. This is done on most boats by the reef points where the sail
gets tied around the boom. I have not yet figured out a way to do
this or even if it is necessary.

Frogwatch