Izzy was clicker trained from the beginning and I love it and after a while you can slowly phase out the clicker. But just the other day when she was obsessed with the squirrels outside and would not come in I got got out the old trusty clicker and wham she was in the house faster than lightening..since she knows she gets a special treat then.
I love Pryor's site since they show actual videos. Trust me it won't take long to train your baby..they get to know that sound pretty fast.
My advice is to keep the treat special and only use for clicker training.