There were times that Sherlock wished he had done something different.
Actually, this was a lie.
Sherlock never regretted anything. Regret was a waste of time and energy, a drain on precious resources.
Yet.
If he could turn back time, there was one course of action he would most definitely change, even though he had had no choice in the matter at the time.
He would never forget the reaction.
Sherlock honestly thought at one point that John was going to have a heart attack. He was unsteady on his feet and so obviously in shock.
The longer John stood there without saying anything, that inscrutable look on his face, the more Sherlock began to realise This Was A Very Bad Idea.
When John thumped the table with his fist it was confirmation that maybe, just maybe, this was the one time he had completely underestimated how the other person would feel.
And he would underestimate. After all, he'd never had a friend before. It was novel, and he was still feeling his way around the mere idea that another human being considered him a friend (and not a freak). So often Sherlock had no idea how to act and had relied on John telling him when it was too much, too far.
It was obviously too much and too far for John.
As John tried so hard to control his breathing, his anger, Sherlock tried to lighten the load by asking about the moustache…and the hands around the throat told him it was Even Worse Than He Realised.
So, they went to the local chippy to talk. Sherlock wanted to explain, he needed to explain. He had really missed telling John how he had worked everything out, to share with John that euphoria of how he had outwitted someone, and not just anyone – Moriarty! He had outwitted him!
He was shocked that John wasn't interested in that fundamental of their friendship. Perhaps Sherlock had to consider that two years apart had changed that dynamic. When John had said he wanted to know why he wasn't told, Sherlock hesitated.
Telling him that Mycroft knew seemed to be alright, but when he mentioned that there were others that knew, and John sighed, Sherlock knew this wasn't going to end the way he had envisioned.
When he admitted it was Molly and around 25 of his homeless network, and John went for him – again – Sherlock considered he had been lucky.
It wasn't the first time he had ever been punched, nor would it be the last. But that one punch hurt more than anything ever had.
And of course, Sherlock being who he was – a completely honest moron – had to tell John the truth. The resultant shouting was almost amusing.
So yeah, if Sherlock had a time machine and could travel back in time, he would definitely change how he told John.
He would make damn sure they spoke in a quiet place, not the chippy. Because, honestly, what was the good of 'still being dead' but letting John know, if John was going to shout it out to all the world?