So, I have searched the focusfanatics forums very thoroughly, and I feel pretty confident even without inspection that the problem lies within the master cylinder.
Focusfanatic Grumpy said it best, in my opinion:
"If you can get the pedal hard by letting the pedal up and then quickly applying the brakes again, it ain't air in the system, but assuming there are no external fluid leaks, you've probably got the master cylinder bypassing fluid (fluid leaks past a piston seal). Usually will be noticed when applying the brakes for a relatively long time, and the pedal will slowly drop towards the floor. It IS NOT normal. Get to a dealer.......the warranty should cover it. It is not normal wear and tear on the brakes."
However I would like to avoid the dealer if possible. Does anybody have any experience with replacing the master cylinder on an '05 Focus? Is a pressure bleeder or specialty dealer tool really necessary?
I actually don't mind spending the money on a pressure bleeder since I'll probably come out ahead of a dealer repair bill anyways, I'm just wondering.