After a short period of using the system, all but one of the participants in the user testing settled into a style of working in which they would write the entire formula, then go back and make any necessary corrections. This style of operation proved to be a more efficient and comfortable method of formula entry than stopping to correct any grouping or recognition errors as they occurred.
This working style may have been partly induced by the fact that the system required the user to interrupt the flow of drawing in order to press a button on the toolbar, to change the system from drawing to one of the two correction modes. Had it been possible to correct mistakes without having to go through a ``change-mode'' step, this working style may have not been so prominent.