thats very true although i tend to find a more 'hands on' approach works better for me than the help of dvd's! (all in the cause of learning how to ride of course!) - oh god this post is getting bad!
oh of course, equal dexterity of both hands would certainly be a better experience for both mount and rider. its also helps the rider if the mount isnt 'dead to the leg' as you dont want the performance leaving you both sweaty! - although....in some cases this can signify some good work has been done.