User blog comment:Blackendedsoul/Strange Behavior/@comment-7890302-20140516012112

Well, humans are not defined by one track minds.

Most of these, are made at the heat of the moment. BlackBeard declared when he could have won, when he killed Whitebeard. He just killed the world strongest (Cowardly, after Whitebeard had a bunch of strong opponents take a piece of him, and being shot and stabbed a few dozen times by the best of Level 6), he thought he could. Besides, it has less to do with power, and how effective they are. Maggelan, has a Hax fruit, that can poison anyone. Logia, or not. Pica can shift the stone, and thus, most of the opponents were on stone. Besides, even Level 6 guys may not like being dipped in hundreds of vats of Lava.

It can be strange, but explainable.