Silver CAN and DOES hide on red-based horses. Therefore I personally do not consider it incorrect to whoever calculated based on possibility of silver as the cremello would be red-based and therefore not display any outside signs of silver. Silver affects and often restricts the black pigment but leaves the red be. This is why there is no such outward colour as a 'silver chestnut' but silver bay and silver black crop up fairly often.
It is the same with Agouti. It does not affect the red pigment, only restricts the black pigment, so a chestnut can have Agouti and not show any signs. Mum bred a chestnut stallion to a true-black mare and got a bay foal. It can and does happen.
Last edited by blue eyed pony; 08-21-2011 at 08:08 AM.