Not sure if you know this, John of course is a very seductive lip licker which gives us 'those moments ' when we know that he is in an interesting place in his head.... but is this a john thing or a Martin thing? I've been watching out for it in other Martin roles but don't see it so are those lips licked just for Sherlock ? Wow that's a mouthful to say!! Haha
You know what? I actually think this is a Martin thing, because I have seen interviews where he does it, as well as in a few of his other roles. But yeah, I feel like its a conscious decision on Martin’s part to make John an obsessive lip-licker, especially around Sherlock or when he’s thinking or talking about Sherlock.
John is very… unapologetic in his desire for Sherlock. I think though, on Martin’s part, he made this one of John’s “unconscious tics”, like the hand clench when John is stressed or hiding his true emotions.
Martin is a brilliant “micro-expression” actor; it’s why his John Watson is so amazing.
That all said… WHY make John obsessively lick his lips around or when thinking about Sherlock if not to show John’s possible attraction to him? Well, I mean there are other reasons: I guess John just has really dry lips. All the time. Especially around Sherlock. Someone get that boy a chapstick.