Nodak, thanks for your vote of confidence. As I said and will reiterate I think the Gale Sail is expensive. It sets and strikes with a lot of friction on your other sail, and in conditions in which even a little abrasion is a bad thing. And it is a product, easy to see, buy, and own; but as with so many things in sailing the better answer may be in the adopting of a process rather than in the possessing of a product.
You raise the question of, 'is it really necessary to take off the genoa.' My answer-- absolutely.
Personally I think in some cases roller-furling (they're not called 'roller-reefing') jibs are a crutch. Think about it. Is it there to contain the most-used headsail in your wardrobe for the next pleasant day you go out again; or is it there for you to forever avoid the 'hassle' of taking it down and hanking it on and off? If it's there to keep you from doing something that's otherwise necessary, it's a crutch and you're living in denial. This is never good. (I feel the same way, only more strongly, about in-mast mainsail furling.)
I asked my FLS (friendly local sailmaker) Skip Moorhouse, an old friend and admirer of my dad and original owner of Hunter 25 hull #1, about having my current hank-on jib converted to #5 luff tape so I could use a Schaefer Tuff-Luff foil. The Tuff-Luff is like a furler foil but without a furler drum. It has 2 grooves and its purpose is to be able to hoist one jib while the other is still up and drawing so to avoid being 'bald-headed' during a race. I have sailed often without one and recognize its value. Skip said, forget it, 'whatever was the matter with hank-on anyway?' And I see his point; he's encouraging me to stick to round-the-buoys racing and mild cruising. But I intend to singlehand this boat and would like to be able to hoist one before setting the other, just to save time, as the process of changing headsails is much slower when you are the only foredeck/halyard person and you've got to bag the one before pulling the other one out of the hatch and by this time the boat has wrenched herself round into the wind and all hell is breaking loose with the breakers over the deck and... you get the idea. So I am sort of committed to the Tuff Luff.
The principle behind taking the genny off the furler is the same. You are stuck with the biggest and lightest sail in your wardrobe on that thing, utterly useless by the time you must put in a main reef. Is anyone going to say with any credibility, 'well in conditions like that I won't be out; I'll be at the dock with a cocktail.' etc.? You'll be surprised how often that is pointless when the squall comes up on you by surprise.
I once saw three guys on some 33-footer trying to make the channel in the Chesapeake Bay Bridge/Tunnel under furling genny alone. They had got scared in the gusty conditions and furled the main; but now they could not point because they had no tendency to weather helm. As I watched they blew more and more down south in the westerly and finally threw a tack that put them on a course back to sea, and if they threw the next tack any earlier than like OCEAN CITY, they would be on no better of an angle 18 hours later. I was to the point of yelling, 'Change the jib!' and 'Pull the main up!' when the kids came and got me.
Certain phobia have no place in sailing-- especially when the recourse is to learn the boat a little more. Don't get me wrong-- I won't pretend I am immune to either fear or stupidity myself. But that's no reason to justify either.
Learn about the furler, find out how to pull down that sail, and put up another one, and use that otherwise handy grooved foil for much more than most people do. And remember Jerry's boat in our yard, ready to blow off its stands in 60-MPH winter gusts (it scared the crud out of me to see it. My boat was just downwind of his). Taking that sail down is sometimes (often) your only truly safe and sane course.
Alan says changing sails should be like MOB drills, frequently practiced. In a conversation at my club we discussed this and I said (with my big mouth) that with your usual crew you should be able to slab-reef the main to the first reef point in 60 seconds, or practice till you can. The other club big-mouth said, 'Or 45 seconds.' I had to eat my words then-- and gladly, for he is right.