The Phoebe Chronicles XIII: A Brick and a Click

Then Kay took over. She placed the brick again in front of Phoebe. Phoebe approached the brick, about to repeat the behavior but got a click before she got there. Kay kept clicking on Phoebe's approach to the brick, rather than for the desired ultimate behavior. What was she shaping? The slant of her shoulders and shift of her weight. Kay was marking Phoebe's muscle movements so that when eventually she did place both paws on the brick she would already be balanced and in perfect position; Kay was polishing the behavior before it was established.