It's probably good for their relationship, such as it is, that neither of them is all that interested in what the other one is doing when they have something more appealing going on. In Long's case, it's sleep. In Sherlock's it is quite literally adventuring.
Sherlock pockets his own tablet and sets off for some preliminary bad decisionmaking.
[text]
Sherlock pockets his own tablet and sets off for some preliminary bad decisionmaking.