The two things are linked because a buzzer-beater was needed in part because of Wade's poor performance. This is in essence why you said Tannehill's performance "won't be enough going forward," because you can't rely on the equivalent of a buzzer-beater in terms of improbability (i.e., Derrick Henry's over 200 total yards, the opposing QB's poor performance, etc.) every week, to overcome that degree of poor quarterback play. If I start a fire and then grab a hose and extinguish it, I still started it. Again, Tannehill's performance wasn't "harmless." If the question was whether he could make single positive plays in a difficult playoff game, then I'll agree, he answered that question affirmatively. If the question was whether he could play overall in the playoffs in a way that's associated with winning, he still has to answer that one.