Well, hopefully, this interesting thread topic will get us all to think a little bit more about it
That is basically what I wrote about in the Ouch! thread.
I actually did not at first breed my bitches to Silverback as much as my other stud dogs, precisely because (as you say) he was "different" from my regular Poncho dogs. However, after thinking about it deeper, and realizing he was adding something BETTER that my dogs never really had before, I shifted all of my breeding focus on putting my good Poncho bitches under Silverback (beyond all my other studs) ... precisely because Silverback was giving me two key traits that my other studs could not give me (while losing nothing of the common foundational traits I have set in my family and come to love).
And now, having done this for a number of years, I can say that (so far) the dogs who definitively carry Silverback's finishing trait also definitively carry his color (and, similarly, almost all of the very best Poncho "head dogs" were buckskin dogs with a black spot on their tail, like Poncho)
However, again as I stated in my first post, this does not mean I believe color and ability are "always" (or necessarily) linked ... but I do believe that, if you're family-/line-/inbreeding, that the dogs who come out with the color and the other defining characteristics of the main dog they're down from are simply more likely to carry his key performance traits that you're breeding him for as well. And anyone who disagrees with this simply has NOT bred a family of their own dogs long enough to have a valid opinion.
Therefore, to answer your question as to whether to go with the new-colored dog or not, that would depend entirely on whether he was adding something better or not.
Jack