Bad idea to winch the furling line. It's not a large line for a reason. A winch is more force than you should need to use.
The extra force of a winch is not in the direction that is best suited to the forestay. The forestay is very strong in tension (supporting the mast) but not well suited to large perpendicular shear forces (your winch pulling the furling line) all at the same time.
Your winch can make a great deal of force many times greater than a very strong human can pull. When sheeting in a jib
strong this might be thousands of pounds of force.
sheet is larger than your furling line for a reason and you are using the same mechanical advantage on a line that isn't near as strong and concentrates all your effort in a shear direction at low point of the forestay. Meanwhile the wind
is pulling on the forestay to hold the mast
too. You have just too many large forces in multiple directions to avoid a serious problem.
when it's too hard to pull by hand. When it luffs you'll be able to pull it in as required. You'll treat your rig and gear
more gently doing so.
I had a halyard
wrap at the top of the mast
, then break, and unlay the top of the forestay (9/32 in cable) so it looked like a cork screw doing this very thing. I'm pretty good on a winch
I'm telling you is a bad thing to do because I found out why in a big way! The forestay didn't break (was replaced later). Your winch is far stronger than you realize.