"Not last time." This is, oddly, said without any of the malice of the earlier statements. Instead it seems like a genuine fear.

Howard short enough, and Sherlock tall enough, that his heels don't totally hit the ground when he's supported.

"His limp's back." It feels like one of the things he can say that would indicate John's not alright without talking about how he's watched John sleep when he was allowed to stay over. Even he knows that's creepy, though he feels like he can't help himself. John never even told him the limp was a psychological thing, but Howard's observant.