To begin with, it’s “bated” as opposed to “baited”. “Waiting with baited breath” is clearly rather nonsensical. You’re waiting with your breath set as bait in a trap?
Bated is an archaic, abreviated form of “abated”. So, “waiting with abated breath,” essentially means that your breath has lessened, or likely stopped, because you’re wracked with nervousness or fear. Essentially, you’re holding your breath.
So another common idiomatic expression, for the sake of consistency, ought to have been phrased, “I’m not going to bate my breath,” when you don’t think something will actually happen.
It’s weird how idiomatic expressions linger in a sort of timelessness when usage has otherwise rendered a form archaic. I suppose it’s because people say them on cue without really thinking about what they mean. Like saying “Bless you” when someone sneezes. Maybe I don’t want to be blessed?
The people of the future will be trying to figure out what “Git ‘er done” means. Actually, forget that– I’m still trying to figure out what it means.
Anyway, keep that breath bated, today is do or doom day. FAA oral exam and checkride in a few hours. Well, unless the weather turns to crap, which looks rather possible. I hope that I won’t suffer from checkrideitis and forget something really stupid like the landing gear.
(And it’s not really potential doom, I’d just have to review whatever I screwed up and do it again.)