The problem is the system lets your time running without delivering opponent's move. It is clearly against the rules of chess and unfair. Usually there is no sign of your own disconnection, it looks rather like opponent's disconnection and/or time manipulation.
Hum... I guess you mean that when you disconnect, you don't get a warning, whereas your time is running low on the server.
It doesn't deliver the opponent's move, because you disconnected, duh. It might seem the opponent's manipulation, but again, it really is your poor internet connexion. The opponent has lost time when he was thinking, does not lose anymore now he gave his move to the servers, and has no way to influentiate on this. I don't see how this can be unfair.
If you mean it would be better to have a warning such as "beware, you are now experiencing connexion issues, you might be going low on time without knowing it", let's say you are right. Still, it doesn't change much.
It's not cheating. Plutonia explained exactly how it happens, which ends up being your own fault for having a bad connection.
That's being unfair, not everyone lives in a country with good Internet options.
...and ?
This is the only way to keep people from really cheating by artificially disconnecting to take more thinking time.
It's like saying chess.com is unfair because it is accessible only to people who have an Internet connection.
The problem is the system lets your time running without delivering opponent's move. It is clearly against the rules of chess and unfair. Usually there is no sign of your own disconnection, it looks rather like opponent's disconnection and/or time manipulation.
I retired from Live chess a few years ago because of this. I always checked my connection and it was OK, so it was on the server's side I suppose.