How to tell co-worker he has gross eating style?

I was thinking of an anonymous letter on the desk, so there's no confrontation. Bad idea?

Dear X,

I'd like to discuss a sensitive topic with you. I do not intend any disrespect. Instead, I mention it in a sincere desire to benefit you.

Different cultures have different norms when it comes to eating etiquette. In mainstream Canadian culture, it is generally considered to be quite rude and crude to make excessive noise while eating. This is especially true of wet lip-smacking noises, and slurping. I understand that in other cultures these gestures are in fact encouraged, and show an appreciation for the meal.

I recognize that you are someone who cares about his appearance. You are always well dressed, and well groomed. Be advised that you may be unintentionally undermining your image by eating in this way. Obviously, you are not intending to offend.

I'm writing this in a spirit of helpfulness, and truthfulness. It's an uncomfortable topic, but I hope that this information is useful to you. Often in these situations, others will never say anything, because they are too afraid of being rude. In that case, people never get feed-back they can use.

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