Logging in is trivial and means nothing. It doesn't mean that someone is actually reading anything or available at that time.
It means something.
- got access to his account
- got Internet
- is mentally fit to remember passwords so probably could write a post
- has time to log in and out
Not really, no. This is you making conslusions based on putting yourself in this scenario. I log in without 'remembering' or even knowing my password for example.
If you can log in (and sometimes even post) you can certainly post an update as well, here and there.
Not necessarily, no.