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Just to confuse things further: I've never used any sort of solvent wipedown on bridge bottoms, and never had a problem that I could attribute to contamination. I have heard that wiping down with a solvent merely spreads the stuff into a nice even film....
Working time with hide glue is less of an issue than it seems. Remember: what counts in the end is how much dried glue there is in the joint, how you get there is a variable. By choosing your path correctly you can greatly extend the working time.
My feeling is that the usual recipes for mixing hide glue are predicated on cabinet shop practice: joints that may not fit perfectly and _lots_ of clamps. Back in WW II the Forest pProducts lab decided that 125psi +/- 10% was the 'proper' pressure for clamping. Considering a normal C-clamp will give you 300# or so, that's a lot of clamps for some stuff. Let's not even get into go-bars.
I once demonstrated a 'rub joint' with hide glue for a friend of mine. I dressed off a leftover brace stick with a plane, snapped in in half, spread some hot glue on the surfaces, and rubbed them together until it grabbed. Then I set the pieces down to dry. This is a common way of joining tops and backs for fiddles; you used the gelling and shrinkage of the glue as a 'self-clamping' mechanism. About 15 minutes later I clamped one of the ends in the vice, hit the other with a hammer, and got 100% wood shear. That joint was not clamped _at all_, let alone for the 2 hours you normally would allow.
The trick is that the rubbing removed the excess glue, a job that is normally taken care of with clamping pressure. In this sense, then, you can say that the real function of clamping is not to put pressure on the joint, but simply to reduce the amount of glue in it to the proper thickness. The thicker you mix the glue, the more clamping force will be required to do the job.
Lots of pressure works out great on normal garden-variety cabinets, where the joints might not fit as well as they could: I'm not talking about the high-class stuff here. Even there, though, it's possible that you'd have to use a certain amount of clamping force just to pull things into line if they've warped or whatever.
We work to much closer tolerances, if we're doing it right. We don't have to rely on clamps to pull things into line: if they don't fit with just finger pressure they should be re-worked until they do. Thus, IMO, we can usually get by with a much thinner mix of hide glue than the label instructions say.
With a thinner mix you get the advantage of longer working time, at the cost of having to be more careful about 'starved' joints. So far the only time I've had a problem with starvation is when I warmed the joint up too much and for too long, and used a lot of clamping pressure. I was just learning then, and haven't had any trouble since.
It's easy to tell when you've exceeded the working time of the glue: it changes from honey into toothpaste. If that happens you just take everything apart right away, wash off the glue, and try again. Alternatively, you can use something like a hair dryer to warm the joint until it turns back to honey again, but there's always the chance there that the heat did not penetrate enough, so this takes some experience. Pre-warming the joint helps, but don't get it _hot_.
Pre-positioning your clamps and having everything handy _before_ you spread the glue is important, even with Titebond. I have all the cauls taped in place, clamps inside the soundhole, and paper towels and straws for cleanup handy before I open the glue bottle, at least when I'm being a good boy.
In the end, as with so much of lutherie, there's a lot of 'getting the feel' involved. I was taught to work with thin hot glue before I ever read the label recipe, and was surprised at how thick a mix that makes. With properly fitted and clean surfaces, and a little thought, you should be able to do anything with hot glue. Torres did.
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I once was prepositioned by an English teacher, does that count? 