There's normal table manners and then there are "refined" table manners, depending on the culture. Most people do fine with normal table manners. The MC is going to something a lot more strict. Not just sitting up straight in a relaxed manner, but sitting up abnormally straight.
For an example in my life, I went to this one place where as some random side thing, they had some elderly mentors teach us etiquette. One of the table manners was to slice meat in one direction, going outwards. So sawing was not allowed (going back and forth). Cut outwards, lift up the knife so it is no longer touching the meat, bring the knife back to the beginning, and then cut outwards again. Like some sick joke, for our meal, they gave us cheap butter knives to cut some of the toughest overcooked slabs of steaks ever. So of course we were failing miserably to cut the steak. During the meal, whenever the mentor looked away, we would furiously saw away at the food in a way we never would normally do and then immediately stop and resume the "correct" way whenever the mentor turned his attention back to us. That's just one of the ridiculous etiquette rules.
Ah.
See, the trick is to put all the pressure on the tip as you push the knife away from your body, amd you use no force when drawing it back; then (in the US, but not in Europe), you set the knife down, and switch hands, while placing your off hand in your lap, place the meat in you mouth, place the fork down on the other side of the plate from your knife, and chew with your hands in your lap.
Only after you swallow do you take a sip of wine, and engage in conversation.
Basic manners!
And obvs that you sit totally straight when at the table; it shows basic respect to the presence of others seated with you.
I'm just confused that this guy considers this to be "hardcore;" this is just how civilized humans eat, as far as I'm aware.
I've known this stuff as the absolute basics of basics, and I've never had more than 3000 dollars American to my name at one time; not ever.
I've been poor my entire life; my kids ate breakfast and lunch at school, and my spouse and I only ever ate dinner for most days... because food costs money, and there is not enough food stamps to feed a family, so... anyway, I've always been poor.
But even being lower working class, manners like these are very VERY basic; I seriously thought everybody knew them.