proper Sail use

[AdamLein]

Colin: sounds like your point 1 is more of a good-seamanship issue than a purely mechanical issue. Similarly the issue of the mainsail sometimes shadowing the jib - that's a decision you make (like I mentioned when flying the chute).

Your third point is interesting and hadn't occurred to me. I guess what you're getting at is that foreward forces on the mast are countered not only by the backstay, but also by a tension which is transmitting through the mainsail and boom into the mainsheet? While I suppose I would rather blow out the leech of my main, burst a fitting on the boom or traveler, or break a mainsheet (?!?) than lose the mast, I expect that in conditions where having a "second backstay" might help will be ones in which you want to reconsider having full sail up. And if you're reefed, that changes the mechanics significantly and I don't know if you'd still have that "second backstay" effect.

Another issue there is that when you're close-hauled my understanding is that the sails are mostly providing lift, which acts in a slightly foreward but mostly athwarthships direction. In that case what you need is not an extra backstay but an extra windward shroud...

[marujosortudo]

Agreed on all points.