"OH, You should never put a furling line on a winch !!!!"
They just didn't know what they were talking about. After all, how would they explain electric and hydraulic furlers? Or how an electric or hydraulic furler using a motor to turn a furling drum (well, the torque tube in these cases) is different than a drum line on a winch?
And obviously neither of them have been on a boat larger than 40' or so. Or they are true gorillas.
When the wind pipes up and it's time to bring our 1000 sqft screecher in, there is no amount of easing it or going downwind where the first 25-50% is easy to furl by hand. Same with the 560 sqft genoa when it is time to reef in 25kt winds.
The "never use a winch for a furling line" is just unexamined dogma. It has never been a part of manufacturer's instructions, nor anything people who sail on larger boats or in challenging conditions have ever paid heed to.
Anyone who has ever used a winch, even an electric one, can tell when something isn't going right. Why would a furling line be any different from a halyard or sheet in this regard?
Mark