People learn not to clutch at their brakes if they are covering them. But if they don't cover their brakes they tend to grab the bars and then need to release before they can pull their brakes. In an emergency this can be a significant delay in their ability to stop quickly.
Factors affecting higher-order movement planning: a kinematic analysis of human prehension
LS Jakobson, MA Goodale - Experimental Brain Research, 1991 - Springer
People learn not to clutch at their brakes if they are covering them. But if they don't cover their brakes they tend to grab the bars and then need to release before they can pull their brakes. In an emergency this can be a significant delay in their ability to stop quickly.