Using an ability while lagging does not apply the ability but initiates the cooldown.

Time: Tuesday, October 29th at 2:30 pm EDT
Frequency: Random.
World name: Sargatanas (Duty Finder)
Character name: Ceol Ashwin
NPC name: n/a
Monster name: n/a
Class/Level: Paladin/50
Party or solo: Party
In-game time: n/a
Area and coordinates: The Wanderer's Palace
Steps:
1. Have a client-side connection issue resulting in a lag spike.
2. During lag spike, while no one is moving and damage does not apply, use an ability with a long cooldown (for instance, Sentinel.)
3. Even though the ability's effect is not on your status bar, the ability is unusable due to its cooldown having started. I believe this is because the client does not check with the server that the ability has applied successfully, so it just initiates the cooldown regardless.

Connection Specs
- Comcast Internet (Central Maryland/Washington D.C.)
- Motorola

Model Number of the PlayStation 3 You Are Using
- Model Number: Original 60 GB "fat" PS3

Greetings Ceol,

We appreciate you taking the time to report this concern you are having to us. However, since this sounds like a technical issue rather than a bug report, I will be closing this particular thread. We welcome you to post about this concern in the "Technical Support" forums.

- Furlamseere