Re: DDW and bailing out
Maybe it's just me, but I am not a big fan of preventers...
I sail shifty air a lot, and 90 degree shifts are commonplace. A preventer would keep the boom on the correct side, but perhaps at an exaggerated angle to the wind, causing excess heel, or worse broach.
The simplest/safest thing is to "chicken-gybe" and do the 270 to change direction...
But the RIGHT way, would be to "soft-gybe." Sheet in the main, lock the traveler amidships, start your move through the gybe, help the boom over. Coming from DDW to broad reach. We had to do 2 of these at the last couple hundred feet in our last race, in decent winds with 155 genoa up... It helps to keep the communications open with the crew (even if they are slowed with alcohol).
Accidental gybes are dangerous for every reason stated above... it's breaks spars, rigging, knuckles, and heads. It can swamp and or broach boats too.
For the record I try to avoid Wing on Wing as the winds pipe up mostly do to those 90 degree shifts I have to live with... but NOT practicing what I preach, we did a short stint at the end of the last race Wing on Wing, as well as 2 gybes. Crazier than that if the "RUN" had been longer, I'd have thrown the Symmetric up.
S2 7.9 - cheap, fast, trailerable, and paid for.