A lesson that Claudine Collins, the MediaCom press director, also learned last week, but luckily not on such a scale that she lost her job.
Responding to an e-mail despatched to dozens of industry luminaries by Simon Davies, the ad director of The Mail on Sunday, Collins was rather coy in responding to an invite to a posh bash.
Despite Davies offering free dinner, followed by a piss-up at the Metropolitan Hotel's penthouse, Collins replied with: "Depends how drinks on the 31st goes!!!! X." The only problem? She also sent the mischievous response to the other 43 recipients of the e-mail.
Now Diary doesn't know exactly what Davies has planned for Collins on "the 31st" - maybe he wants to have a conversation about his loose inserts - but other recipients of the e-mail, including Media Planning Group's Mark Craze and Zed Media's Greg Grimmer, are keen to find out.
It may just be that the pair plan to thrash out the terms between The Mail on Sunday and MediaCom's clients. However, rivals will be desperate to know if Collins is receiving any special treatment.
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