Usopp really didn't learn anything these past 2 years. He's the same unreliable coward with some new moves.
This episode reminded me how much I hate his fights. First he runs away, then he will do his desperate fight speech and he will win by pure luck.
I really hoped he changed a bit after the 2 year gap.
It's not only him, but the other 3 cowards of the crew as well.

In ways of storytelling, it's lazy. Have the balls to make your main characters grow during the series.