[Callaghan's only ever followed his own patterns, which, to a degree, are predictable. he does what he believes is necessary, whether it be taking a firm hand with his students, doing a little bit of manipulation to help them get over themselves, or setting a fire to cut himself off from everything that could have gotten in his way of closing an unpleasant chapter of his life. when stressed, he tends to simply things - perhaps too much - and with the 'threat' of Baymax being pulled in (even if he /is/ going to come, sooner or later, a simple fact that Callaghan has come to understand and perhaps not accept but acknowledge), he's trying to simplify what he can.

but as a man of science, Hiro's lack of attention to detail offends him. the narrowing of Callaghan's eyes is solely because if any of his students had given him that vagueness, he may have assigned them some extra work because clearly they weren't doing enough on their own. they - and Hiro - should know better]

Start a log. Time, date, any and all circumstances you can think of. Or find out if your brother already has, because if he's not doing so then he's slacking off.

[he raises a hand to point, and the microbots make their own sort of gesture in accompaniment...before pulling right back to him as he lowers his arm. they've taken to a slow flexing and curling, a tight writhing that only ever goes so far away from his body. it's almost as though someone was constantly working their fingers in to and out of fists, but for the most part, they avoid moving towards Hiro- Callaghan's attention seems to be inward enough that they focus on /him/]