Ah, the Sinister Sales Engineer. Many companies have one. Early in my career, when I was not even a "Senior" Product Manager yet, this guy scared the bejeezus out of me.
Let's just say that this guy was from the Bronx and had an, ahem, "way with words." Especially four-letter words, and words like stupid, brain-damaged, idiotic, f$%#ed-in-the-head, and you-f$#$ing-moron.
He got away with this type of behavior because he was in Sales and He Could Close. And if you're in Sales, that is all that really matters - HR Handbook and Employee Code of Conduct be damned.
Anyway, without fail, the Product Team would announce its product roadmap, the details on a new feature, the release of a new white paper - whatever. The Sinister Sales Engineer would listen to our enthusiastic spiel, and then he'd ask three or four incisive-but-damning-and-sarcastic questions that would make all of us feel like the biggest morons that ever lived. Then, unsatisfied with our bumbling answers, the Sinister Sales Engineer would actually SAY, in front of everyone, "you guys must be some of the biggest effing morons that have ever lived."
And the thing is, the Sinister Sales Engineer was usually right. Argh! We made countless last minute changes, and endured countless humiliations because of this guy.
But looking back, I can say Thank God we had him, because we put out better products as a result and he really made us up our game. But at the time I was absolutely terrified of this guy.
After a while, I learned how to handle him. And if you have to deal with an Sinister Sales Engineer, I encourage you to do what I did:
Practice Gratitude and be thankful that you have an Sinister Sales Engineer. You will produce better products because of him/her. He will speak the truth you need when everyone else is being polite.
Call the Sinister Sales Engineer a few times a month to get his/her feedback early and often. And let him/her know that you appreciate the brutal honesty.
If you occasionally act on the feedback he/she provided, over time the Sinister Sales Engineer might actually start to respect you. The public lashings might even dissipate, although they will probably never completely disappear.