I haven't done it and don't want to. But glass will not overpower good compression woods such as osage,yew,ipe etc...one of the reasons why you don't see it much is because to a lot of folks its not a harmonious marriage. Most wood bow makers back there bows with natural materials like another piece of wood,sinew,rawhide,silk,etc..,and totally detest putting something "unnatural" and man made on something that is naturally made. If you put glass on the back then its best and better to put it on the belly as well.