Re: the bar to saddle drop question, I'll take a stab and let Margo correct me.

Fit is all about the angle in your hips and shoulders. If you look at someone who has been properly fitted on a variety of bikes, the angle of their back/hip and then their back/arms stays relatively the same. It doesn't matter if they are on a tri bike, road racing geo, touring geo, etc. Those angles will stay about the same.

So, if your bike's geometry isn't designed for a saddle/bar drop or vice versa, you aren't going to get comfy. Take a tri-bike, you should be sitting farther forward over the crank than you would on a touring bike which means the seat tube is a different angle. This also means the front end has to be lower and longer.

There's my very garbled take on this.