JoAnne, clicking isn't just for new behavior - that may be part of your confusion. The clicker provides information to your dog. It tells your dog
YES, THAT'S WHAT I WANT!! There's no hard and fast rule, you don't have to fade the clicker after "x" number of sessions. I still do sessions and use the clicker for really simple things like a good 'sit' etc, simply because my dogs enjoy hearing that 'click' - it excites them, they know they've done a good job, and they know a reward is going to follow any second. That 'click' makes them happy, and keeps them working.
I believe you said you ordered Gail Fisher's
The Thinking Dog a few weeks ago (am I right?). If so, check out Chap 8 on Building Behavior, and you might get some of your questions answered and things clarified. I think she explains what the clicker is really doing, what kind of info you can provide with it, how to vary your reward and rate of reinforcement, all kinds of things. I know, I know ... more to read.

I think it may truly help to clarify things for you, tho - kind of help to put all your ducks in a row so things make sense for you. Who ever thought one little noisy piece of plastic could cause such stress, huh?
To answer one question you asked, you wouldn't 'click' if Asher gave you a "half-assed" behavior. He'd get nothing, or maybe a "whoops", or "that's nice", but no reward, if he's just kind of slopping thru stuff. You'd wait for that good, sharp behavior, then click/treat. If he's kind of having a hard training session, and finally gives you a good behavior, sometimes a jackpot works wonders, and will get them working much harder (cuz who won't work for a little extra?). Just to clarify, a jackpot would be maybe a whole handful of chicken, as opposed to one piece like usual. Think about that from your dog's point of view.
Ok ok, mom wants me to sit and stay, alright fine - WHOA, I got a whole handful of chicken!! What do you want me to do now???? Sometimes a little inspiration goes a long way.
I hope I haven't added more confusion to the bubbling pot.

I know it seems at first like it's just all so complicated - just clear as mud, huh? It will all start to make sense, and it becomes second nature and so simple. Have faith, you'll get it. Hang in there, you're doing great!!