Willy mate, everyone rears their dogs differently. Lilly rears her dogs the way she says and she is very happy with what she does. She is giving you advise on what she does and it sounds good to me.
I chose to give human vitamins to my race dog.I have no problem with that. He has been on those vitamins every day for 12 months now and his blood count is normal. If it were not, the count would tell me what he is lacking and I would ajust my feeding program. I have told the vet what I am feeding him and the vitamins that I give him before the blood count. After viewing the results of the count he told me to just keep doing what I'm doing. So I do.
But remember, he's racing. Thats the way I feed my dog. Other people may feed differently.