I disagree - humor is really useful as a communication tool. If you are naturally inclined towards humor, don't suppress it entirely. I've found it useful once in a blue moon to indirectly make the point everyone is thinking but nobody wants to acknowledge. But more generally I've found it useful to put people at ease at the start of a meeting where I need people sharing ideas and feedback.

In my experience, there are two types of humor that should be avoided, which I learned the hard way:

* Punching down (including joking about doing harm from a position of power)

* Sarcasm/cynicism in public channels, especially when it's directed at specific people/teams.

Disagree. Working at a place where you are or can be genuine friends with coworkers is much more pleasant, and you can't be friends with someone if the only time you escape the sterile confines of the 'all business' relationship is at work parties.

A positive working environment where people can interact as humans do is the grease on the skids of productivity and creativity.

You can certainly have too much "party" in the office. But you can also not have enough.

Check out Humor, Seriously: Why Humor Is a Secret Weapon in Business and Life (And how Anyone Can Harness It. Even You.) by Jennifer Aaker and Naomi Bagdonas