John's advice to take things slowly is as good as gold. I won't think about moving on until my strongback checks out good, re-checks out good, checks out good again, and then just to be sure, gets checked some more. I may spend anywhere from three days to a week dinking with it before starting the stripping process.

I once had a boat that was built on a very slightly misaligned strongback, and lemme tell ya, it ain't a good thing. And NO, it wasn't my doing, but an already stripped-out project I rescued and took over. Tired everything to straighten 'er out, thought I had it, but the stupid thing was just plain bent and you could tell it. That boat's in Guatemala now, one of the few I've ever sold.

When I build a boat, I use a string OFTEN, and I mean A LOT. In the process thereof you can bet I make sure it isn't sagging or anything else because I'm out to create a result that I will never have the least doubt about, ever. I take time to construct good strong towers on which I easily and conveniently stretch, remove, re-stretch nylon string on as much as I want. Which is often, did I mention that?

Remember, no matter how much time you spend futzing with a strongback, it's nothing later, when you're in the cockpit with fifteen miles behind you, ten to go, in rough water with a stout headwind. In fact, the more time you spent, the better feeling it is.

Incidentally, I say rocker trumps waterline. Keep tweaking with an aim to get everything to agree, but in the end it's most important to get fair hull lines, period. Use a strip to check for fairness.