The technique for correcting misrecognition errors, having a pop up menu of the top alternatives provided by the character recogniser and an option to enter the character from the keyboard, worked well. As long as the user did not have to resort to manually entering the symbol's name from the keyboard, the use of the pop up menu enabled quick and easy correction of recognition errors.
Users commented that the pop up menu often did not offer the alternative that the user required, forcing them to manually enter it from the keyboard. It was particularly frustrating for some users to not have an ``obvious'' alternative offered on the menu, but see it filled with a list of seemingly inexplicable alternatives. For example, the top alternatives to a lower-case b often include 4, h, y, and 7. Of these, only the h seems ``reasonable''. The features used by the character recogniser to gauge the similarity of characters clearly does not correspond to the user's perceptions.
The use of a dialog box to manually enter a symbol, or choose from a toolbar of non-keyboard symbols, worked well. An improvement would be to have buttons available for all symbols, so that the user did not have to use the keyboard at all if they chose not to.