Ha Ha, now I'll tell you the truth, That's the theory with grit, I've kept a blind youngster this year, I've only told one person and I'm not mentioning Andys name It has water in front all the time every thing else I feed and it will not touch grit, minerals fine, as you say, I'm sure it's the salt factor, but it has been a revelation to watch this youngster grow every feather and although I've had them for 60yrs. I think I've learned a lot this last year about them and myself