The Donnerhall thread made me wonder about others views on this....
The goal is to go forward and not backwards to acheive the modern horse. I think we all understand that. Are there ever exceptions to this rule?
What long deceased sires would you consider going "back" to and using with your modern mares? Or would you never do this?
Donnerhall, Rubinstein and Florestan would be one I'd use provided I had the right modern mare for them.