[PapaBear]

Excellent food for thought all the way around.
A few questions and observations from the cheap seats.
Dr. Teh has a fine collection of mixed varieties, and all that I've seen look to be excellent specimens. He feeds spirulina heavily along with silkworm suppliments without compromising color quality in the least. (One of my all time favorite Kohaku's is in his pond along with his beautiful Shiro, both eating the same feed).
We know he has great selection skills and good bloodlines, but Koi of excellent lineage often fade anyway if water conditions and feed are not correct so husbandry has to be as good as heritage.
That being said, is it possible that the addition of silkworm keeps the fatty cells underlying the dermis clear and white thereby giving a clear pallette for sumi and hi to be painted on?