Going to windward, "more is less" in my opinion. Over-canvassed to windward is uncomfortable and inefficient. We have a heavy weather 90% jib with a high cut foot. Surprisingly going to windward In anything over 15 knots true it is as quick as the big genoa. But unless the windward work is long the effort of changing sails has me preferring to furl the genoa. .HOWEVER all sails are not created equal. I think this fact is partly why there are such differing opinions.
To have a genoa suitable to furl and use in strong winds to windward it needs to be made for the job. 1) The cloth must be heavy enough.Or be made of a robust fabric 2) The sailmaker needs to know what wind strength the sail will be used in, 3) the sail maker needs to know you intend to partly furl it for strong windward work. 3) The sail needs a properly designed foam padded luff. The cheap option of a rope sewn inside the luff is not acceptable.
Do the above and you will get a sail that will furl and retain a reasonable shape. Light cloth and no foam luff and you will have a sack, not a sail if you try to sail with it partly furled.
I gave Doyles in Auckland NZ these instructions when they made me a new genoa some years back. They used too light a cloth, and refused to put a foam luff in saying the rope option was just as good. The result: In light air up to 15 knots it was a beautiful sail. But in stronger wind a sail that distorted so badly they had to replace it. They fiddled around adjusting seams but in the end I had them on board in only 20 knots true and they gave up and made me a new sail. By the time it was made I was in Noumea and they had to ship it up to me.
Lastly, I agree with the comments regarding halyard tension and car position.
On 13 April 2018 at 22:48 "osterberg.paul.l@...
I’m curious how do you without a stay sail go upwind in true wind exceeding 25 knots, with occasional gusts of +30 knots, in reasonable comfort. We go comfortable up wind in 20 knots apparent wind with the full Genoa, but if gusts exceeding 24 knots apparent we are definitely over canvased. therefore we start to furl just before 20 knots apparent wind. When we encounter apparent wind of 30 knots we found very poor up wind performance with the Genoa heavily furled and VMG is very poor.
Paul on S/Y Kerpa SM#259