I'll explain the system in detail:
The script checks for ping and FPS every 5 seconds.
If it finds a problem, it gives a warning on the player's screen.
Now the player has 10 more seconds to stop their movement.
If your ping or FPS is still bad in in the 10th and 15th second AND you never stopped moving during this time, kick.
I understand that sometimes players get short ping spikes, or a molotov could drop their FPS for a small duration. These players could avoid a kick by simply releasing their keys. So, the people who got kicked were most likely lagging constantly(15th, 20th, 25th...1000th second) and could not afford to stop their movement at all.
Those who played in Vicewar 5, would know that ping and FPS lag was a major issue:
http://viceunderdogs.com/index.php?topic=6511.0