Warning: The following is not for sensitive readers!
I think one can derive this form of ‘Derech Eretz’ from Shoftim 1:6-7:
וינס אדני בזק וירדפו אחריו ויאחזו אתו ויקצצו את בהנות ידיו ורגליו. ויאמר אדני בזק שבעים מלכים בהנות ידיהם ורגליהם מקצצים היו מלקטים תחת שלחני כאשר עשיתי כן שלם לי אלהים ויביאהו ירושלם וימת שם.
Translation from Chabad.org: And Adoni-vezek fled, and they pursued him: and they caught him and cut off his thumbs and his big toes. And Adoni-vezek said, “Seventy kings had their thumbs and their great toes cut off gathered under my table; as I have done, so has God punished me.” And they brought him to Jerusalem, and he died there.
That is, they did to him what he planned to do them, had he won the war.
Lesson: Seeing your achievements during meals makes you happy and helps with digestion, וטוב לב משתה תמיד…
It’s time to study Torah seriously, and learn from it how to live. And to stop believing your rabbis are so much better at this than you are.
Seriously, move your diplomas (if any) from the office (if any) to the dining room (or kitchen).