It is very obviously a manipulative tactic. It is almost at the top, which is the point in time everyone is listening to him. He wants it to be crass because i

It is very obviously a manipulative tactic. It is almost at the top, which is the point in time everyone is listening to him. He wants it to be crass because it is intended to be offensive, not very offensive, but just offensive enough that it sticks in peoples minds for a bit longer. He wants it to stick because it is his only defense and every second his audience are considering how disrespectful he is, they do not think about how he is lying. The problem with "I fucked up" is not the language, it is the fact that it is false. And if congress is commenting on the former, but not the later, it had the intended effect.