While the elder Holmes brother was best known for his affinity towards surveillance, this does not mean that he was the only one of the brothers gifted with such skills. While it was certainly true that Sherlock preferred the less legal routes of gathering information, in this case, Mycroft turned a blind eye and indeed hushed up the almost perpetual monitoring of John Watson by someone not in his office. It had helped that Mycroft had installed the cameras in John's living spaces, no matter where they were.
It had been months since Sherlock had been forced to leave London. Six long months since last he saw his best friend in person. It was hard, even for someone like Sherlock who divorced his emotions as soon as he felt them creeping up on him, and he knew that if the camera lines should be traced, his position would be given away (sentiment is a chemical defect found in the losing side/caring is not an advantage), but he didn't care because this was John.
Boston, Singapore, Lisbon, Cape Town. No matter where it was he was staying for the month, Sherlock was watching John. Watching him cry at idiotic films, watching him go into spells of depression, watching him laugh with the latest girlfriend, watching him talk to the detective who was not there to be talked to. And Sherlock would reply. He'd berate John for being a wuss, try his best to comfort him, point out all the faults of the girl, and fill in the other half of the conversation. And once or twice, when he could tell John was at his darkest point, he'd call him. He'd never say anything, of course, just listen to his friend's voice, desperately trying to interrupt the blackest of moments, to make sure he had a John to come home to.
It became part of Sherlock's mo(u)rning ritual. Turn the computer on, get through Mycroft's firewalls, make his breakfast whatever it was John was eating (he timed it so he could see, and it didn't matter if it was Chinese takeaway at what, for Sherlock, was six in the morning-he ate it), read the newspaper while John was away, all the while wishing he could still be there.
After some time, Mycroft began to get wary, pointing out that there would only be one of two people monitoring John after a tragedy like that, and that it wouldn't be too hard to deduce who it was if the line was traced. Sherlock saw the point in Mycroft's words, but didn't heed them. Sherlock was Sherlock, and if he was anything, he was protective of his best friend. To a fault. He had to know that John was okay, every single day, to know that he was surviving at the very least, if not thriving in adversity as John was known for doing.
