That's the one that messages them when they click it, right?
My guild members found it funny to over use it after I put weird sayings in it. Y'know, over healing themselves and such.
Jerks ;-P. Ya, you can deal with that in a few ways:
1. Blacklisting the bastards so the addon does nothing when they click
2. Lowering the threshold for "wasted" charges below 100%, so when they click it before the fight or when they don't need it it, either does nothing or delivers them a nasty message... depending on what you tell it to do in these events.
3. Instead of blacklisting, you can add the players that like to do this to their own personalized list of messages. One member of my guild liked to to do this, so I added him to a list that would just whisper him "Access Denied" and "Screw Off", among other nasty insults when he clicked ;-P
4. Simply don't use the "use" event to send messages, and instead focus on the Idle event that yells at them after it hasn't been used for an extended period of time :-P. To me, the Summon, Idle, and Personal Use messages are the most important... general use messages just depend on your group, their temperment, and how vindictive they are ;-P