Sweet hay for horses

I have a guy that has been buying my 4th cutting bales of straight alfalfa for his horses to cut down on the grain he has to feed that he trains and was wondering if there is any literature on feeding wrapped hay to horses that I could give him to maybe talk him into trying wrapped hay for them over winter atleast? His horses won't eat the big stems of earlier cuttings, first cutting last year I wrapped and ended up being 23.3% protein so I would think it might be beneficial wrapping the hay to get higher protein and better palatability for his horses. He has over 50 quarter horses he feeds hay to year round and would love to be able to supply him with great hay all year long if I can talk him into this since I don't want to have 3 times the alfalfa ground just to get him enough 4th cutting. Thanks guy!

Sweet hay for horses