One big game does not make a player. But he dominated that football game. I think Warren had questions about his motor too but that didn't preclude BB from drafting him. What it comes down to is the film and the scouting. I think if we can get a Heyward in the 2nd round that is a steal of a value and well worth the gamble. There are not a lot of guys his size who display that kind of athleticism.
So did Seymour, for that matter. Giant college DTs usually do. Few of them seem to be able to keep those big bodies going full-bore every play, all game long. It's the one position where "inconsistent effort" in a draft profile isn't necessarily a deal breaker for me.