This paper describes how marking menus use an explicit recognizer to support menu selection using marks. A key property of the recognizer is scale independence: recognition of marks drawn at any size. We hypothesize that scale independence contributes to fast selections and reduces the effort required. To test this hypothesis, we present an experiment to examine the effects of scale on mark drawing. The results show that smaller marks can be performed more quickly than larger marks but subjects also involuntarily vary the size of the mark, thus giving evidence of the benefits of supporting scale independence. We also present a novel metric for measuring the effort in drawing a mark based on cursor movement dynamics. While this metric is arguably a crude approximation, the experimental analysis agrees with subjective observations.