If I'm killing a man, I'm not intending to be dragging his body anywhere.

[Sherlock has seen what he does when committing murder. John hadn't made any great effort to hide the bodies of the cabbie or that circus bloke.]

I understand your point, though. It was someone with decent upper body strength, so probably not one of the women. That bears out with a death by a blow to the head for the death. [He pauses.] We can probably rule out the dagger for the same reason as the revolver. Leaves the lead pipe, the spanner, and the candlestick. Lead pipe and spanner are gonna be harder to come by in an unfamiliar house... but there are probably candlesticks all over the place.