First I agree with your final parenthetical remark. Still, I think also a pure "yes!" is not a good answer (it might be reasonable as a quick comment). The point is the answer does
in itself not add anything whatsoever. Really the only value of it seems who wrote it and the trust we might have into their judgement. Granted, this can be actually useful in some case,
but it still does not really qualify as an answer. Even if the argument is correct and there is no specific question it is typically possible to say something meaningful beyond yes. And, this better should be done. —
quid ♦ Jan 26 '15 at 17:43