Partial credit to Bucky identifying a problem he's having, but it's sadly not the problem right now.

"I don't care about your competence, Bucky," he practically snarls, "I care that I've known you for nearly five months and no-one saw fucking fit to tell me about it because it was so incredibly obvious to everyone fucking else!"

It's just one more strike against Arthur, one more piece of this fucking place making him useless when he's the only person who can't operate at full capacity around the people he's supposed to trust, because no-one sees fit to tell him even the most obvious fucking details.