Pride swells in Robin's chest, though you wouldn't know it to look at him. His expression looks no more arrogant than is its custom. To have his suggestion not only considered, but taken seriously is a step in the right direction. One towards trust -- or, at least, not away from it. Nodding to show he's understood, he trails Batman like a shadow, showing a rare note of restraint in not belaboring his earlier point, and simply following in focused silence.