"I could, but I'm also making some good points." Not that what Takao says is stupid, just that it seems he wants to fill the silence. What Gokudera says he thinks should be timed appropriately and much more poignant.

It's a practical knowledge, and Gokudera isn't assuming Takao is an idiot... just doesn't like anyone older or younger than him, and doesn't like most people in general. Takao could be the most intelligent person he'd ever meet and still Gokudera would find some way to quietly judge him.

"It just seems too easy." But Takao is making some fair points. Gokudera would have expected some challenges on this quest... something to maybe make him use magic or solve a legitimate puzzle. Maybe the further along this path they go, the more complicated it'll seem.