I know this is silly, but did you notice John’s little stubble in HLV?
It was christmas day, he knew he was going to see Mary at the Holmes’ (he must have known, I mean “these are prepared words, Mary” and all that), he knew he (supposedly? for real?) had decided to forgive her. Nevertheless, he didn’t even shave. John Watson didn’t feel the need of shaving before going to see and express his forgiveness to his pregnant wife.
Do you remember when was the last time we saw him shaving before going to see someone he had already forgiven? Yeah, me too.