Holmes takes the opportunity to let his concerns for the case take over, rather than continue on a conversation with Watson that would no doubt be distracting and possibly a little heartbreaking. He focuses intently on the street instead, looking out the window and watching impatiently for Moran to reveal himself. He still isn't exactly sure how he'll react upon seeing Moran. Logic dictates that he ought to be enraged, or that he ought to at least be able to keep a level head, but after weeks, months of not quite being killed, of seeing his face suddenly when Holmes had had no idea he'd been followed... Moran rattles him.

He hopes Watson's presence will bolster him, and he's very grateful Moran is not as observant as Mycroft, or Moriarty, even. He doesn't want it to be read that he and Watson aren't exactly getting along swimmingly.

His fingers stop their impatient tapping on the windowsill when he sees him. There was never any chance that Holmes wouldn't see him immediately when Moran walked into his line of sight. His blood runs cold, but he keeps a grip on himself, and he backs away from the window. Reaching out, he snatches Watson's wrist and pulls him swiftly into the darkest corner. With his free hand, he presses his finger to Watson's lips to indicate the need for silence.

His other hand doesn't release Watson's wrist. Maybe he and Watson aren't quite able to go back to their romantic relationship, but he thinks Watson, even now, wouldn't begrudge Holmes the comfort that this tight grip is obviously seeking.