Dorrian did declines best chest excercise if if have a weak chest for sure.
I remember a training article way back in the mid 90's in FLEX that showed Dorian doing decline smith machine bench. but it wasn't the exaggerated decline you always see, it was very slight.
So that's what i do sometimes...I'll put a couple of 25's under one end of a flat bench in the smith rack and do them like that. it hits my pecs very effectively.
because it's not such a steep decline that you feel un-natural and the blood is rushing to your head.
It will all be in my book "Nasser's Father"