Perhaps, but I would rather see (heh) the “/u/” thing used instead of “/c/”, unless it is about e.g. a famous person and not a community made by said person. This way there is better distinction between e.g. /c/TomScott and /u/TomScott.*

*not that I expect him here though, given how much he dislikes Reddit. Anyway, it was just an example.

Edit: fixed a typo that made the comment show commas instead of periods in one abbreviation.