My conclusion is because the driver swing has a longer flat point beyond impact,there is probably more supination than with an iron swing but my confidence level with this conclusion is not high.If someone else can make the opposite argument I will change this post. Quote golfarb...
A device for limiting the movement of a player's arm during a golf swing The invention relates to a method and device for resisting flexion movement of a player's arm during a sporting action. In particular, the device provided includes a forearm section configured to be removably attached ...