This very club is pictured and discussed in The Clubmaker's Art 2nd Edition, Volume 1 page 178.  Reference is made there to three other irons with metal added to the top of the hosel.  The added metal served to add weight to the club, even if that was not its express purpose, but the band was most likely created to strengthen the connection between the shaft and hosel. 

This club has its original 39 3/4" shaft and sheepskin grip. It is beautifully made and exceedingly rare. 

This club is the top left club in the group image that accompanies this lot.