To solve the mystery (sort of?) of my last post, I have changed Guinness' feed to help with his foot rehabilitation.
After a lot of thought, I decided to go with Buckeye's Grow n' Win. I have upped hay consumption, and started double bagging the hay to slow down GP's consumption. So far, I'm incredibly happy. My horse is much less stumbling, and more confident in his feet.
Every day I see him walk out sounder and sounder, and my heart beats happier. It's a good feeling to help your animal.