i think regardless of how many bans have been set and how screwy they are, if in any of the modes set that one is superior ie *!*~*@*, ircu wont waste time and effort whilst its being set, but wait till modes have been stopped being sent by the client, then it will work out if they are valid, repetitive etc, then set what it feels is valid bans.
reason: minimizes desync's however I could be wrong but i feel its been written with this in mind. Larry "Yeah well BEAM this up *PAL*!"