Haifagirl, I enjoy your vigilance, your corrections, and your grammatical analyses. It came as no surprise to me that you are also attached to proper table manners, and all sorts of manners. But alas, I must object to one of your pet peeves!
You want to “scream” when someone says “this is yum”? Please. I’m not the first (or thousandth) person to say this, so excuse the familiar phrase, but don’t sweat the small stuff. When someone says “this is yum,” or even “this is so yum,” don’t waste your energy on suppressing a scream. Be happy that you can sit and share a meal that at least one person at the table finds delicious. Taking our blessings for granted and not appreciating our loved ones and dinner/work/life companions is where a lot of impoliteness starts, n’est-ce pas?