A Question of Modern Etiquette

I just now walked into the restroom to rest for a moment, and was unnerved first of all to see that someone had taken the center stall, which everyone should know by now is MINE.

Be that as it may, I walked over to the stand-up conveniences and began my few moments of quiet contemplation, only to have it shattered by the sudden flurry of conversation coming from the center stall. The occupant, you see, was on his CELL PHONE. And he was talking about someone in the LEGAL DEPARTMENT. I mean, I've heard of maximizing billable hours and all, but STILL!

Anyway, I finished up, quickly, and then my quandary arose--does one flush in such an instance, thus disturbing the conversant man on his cell phone, or does one quietly leave, sparing the caller the indignity of loud swirly water sounds, but offending the next person to come in and use the facilities when he discovers the contents of the bowl to be amber rather than restful blue?

Truly, it is a question that only could arise in a highly advanced civilization.

UPDATE:

Although Eric suggested flushing loudly and repeatedly, and I had briefly flirted with the idea of kicking the stall door in and screaming like a lunatic at the man who used my stall, upon reflection I finally settled on this answer.

One must quietly take his leave after washing his hands, and wait in the lobby until such time as the caller leaves the restroom. Upon his exit, without making eye contact with him, re-enter the restroom and flush.

Remember, poor manners upon the part of others is no excuse for poor manners on our own part. Although no one could quibble were you to leave a silent-but-deadly WPD (weapon of pants destruction) before you exit the restroom the first time.

UPDATE the Second: Famous Fritz favors flushing furiously.
posted by Terry at 3:44:00 PM