Actually, it's "no, unless" and "yes, if" that are synonyms. "No, because" carries the implication that the listed justifications are irresolvable.
Re:Can-Do vs. Can’t-Do Culture
by jasonwocky on Thursday January 02, 2014 @08:34AM
(#6999485)
I won't argue that "No, because" and "Yes, if" are mathematically equivalent statements. But I hold that the immutability implication you mention is something added by the listener, not information "carried" by the bits of the "No, because."
They may not be proper synonyms, but a listener that's forgiving of input errors can interpret them as synonyms, at least until proven otherwise through further conversation.
If you let "Yes, if" evoke a different emotional response than, "No, because", even though they provide more or less the same information content, what does that say about you?