That makes sense to me for the kind of food that you cut with a knife. But how does the tines-down approach work for the kind of food that you don’t cut into skewerable pieces, like, say, mac & cheese?
Not all food needs to be cut with a knife.
Some food doesn’t need to be cut at all, because it’s already in small enough pieces when it’s served. Other food doesn’t need to be cut with a knife because it’s tender enough to cut with a fork.
For food that does need to be cut with a knife, I cut several pieces at once, then switch hands and eat them. (I’m aware that Miss Manners would probably frown on this, and if I were at a really fancy dinner I probably wouldn’t do it that way. I also wouldn’t have a book in my other hand, but I often eat alone and I usually do.) I haven’t been paying any attention to which way up the tines are and I think I don’t always do it the same way and that it may depend on the food – I think it may be tines-down for meat and tines-up for something like rice or mashed potatoes. Now maybe I’ll notice for a while which one I’m doing; or maybe I won’t.
It doesn’t.

Some food doesn’t need to be cut at all, because it’s already in small enough pieces when it’s served.
There was a foodie guy who did an episode of his show in China, and the Chinese guy told him, “oh, yeah, we use knife and fork – in the kitchen.” The attitude he conveyed from that was that chopsticks are more civilized: you cut the food when you prepare it, so that it can be properly eaten with chopsticks.

But how does the tines-down approach work for the kind of food that you don’t cut into skewerable pieces, like, say, mac & cheese?
I do not use the tines down approach, but my guess is people who do would say the proper etiquette is to eat such foods with a spoon, not a fork.
On my trip to Ireland last summer I learned using the side of one’s fork to cut foods into smaller pieces is also considered to be very “American” table manners.
What prompted my fork poll was that I noticed, while watching “Chopped”, that virtually every one of the judges eats tines-down.
mmm
Spoon!

On my trip to Ireland last summer I learned using the side of one’s fork to cut foods into smaller pieces is also considered to be very “American” table manners.
That’s weird. Why use a knife if you don’t need to?

“American” table manners
I suspect that in most of Europe and the UK, that is an oxymoron.
Okay, I’m gonna level with you guys. I know the various proper table manners. You could sit me down at a table properly set for a formal multi-course meal and I would sail through it without a misstep. I could also set that table. However, the way I do typically eat dinner is from a plate or, preferably, a bowl on my lap with one fork or spoon. The fork or spoon goes in my dominant hand unless I need it to scroll on my phone.
Etiquette!
I was never taught which hand to use to eat, either. But my parents set the table with the fork on the left and the knife on the right, so that’s the hand i use for each. I’m basically ambidextrous, so swapping back and forth feels really weird to me. Why juggle my flatware as i eat?
You can eat Mac and cheese tines down by stabbing a couple of noodles with the tines. It works fine.
When it comes to cryptids/fraud/thought experimental critters, I draw the line at the skunk ape. I mean, I own snakes and reasonably large lizards (my black throat monitor passed several years ago though) and if kept comfy, they’re largely quiet, quiescent, and easy to deal with. Most of the others are smaller, less obviously violent, or otherwise less disruptive to humans.
But another primate larger than myself? Oh it’s never going to put up with me, or my wife in the house. And that leaves out the obvious issue. SKUNK ape. There’s not enough Glade Plug Ins and Febreeze in the would to save you from 24/7 skunk smell. And unlike the others, that consequence is going to follow you EVERYWHERE you go. Work? “What’s the horrible smell?!?!?! Mr. Lines, go home and only return to the office when you’re not violating the code of conduct.” Fired.
Groceries? Stores? Visits to friends or family? Everywhere you go, you bring the reek of skunk. Your life is over.
I don’t know enough about the cryptids to answer, and I am unwilling to invest the time to look them all up.
I used to be able to ride a horse quite well, so I automatically think I still can. Then I remember that I’m in my 60’s and haven’t sat a horse since I was 35 (and haven’t ridden regularly since I was in my teens). So, sadly, I’d likely be bad at it and I’d know enough to realize how bad I was.
My daughter has been riding for almost a decade, and I think I know pretty well the basics of riding, but it’s still best that I stay down here.
My answer to the “ride a horse” poll would be: I don’t know; I’ve never tried.

Not all food needs to be cut with a knife.
Some food doesn’t need to be cut at all, because it’s already in small enough pieces when it’s served.
Because I use chopsticks, I go out of my way to plate meals so that they are chopstick friendly.

I don’t know enough about the cryptids to answer, and I am unwilling to invest the time to look them all up.
This.
I expect I could get a horse to back up; but that seemed to indicate a larger level of difficulty than to – is that supposed to be ‘change gaits’? ‘change gates’ doesn’t make much sense – with your ass; and while I used to be able to come close to doing that with a horse that was trained and willing, a bit of hand movement was also involved, plus which I haven’t been on a horse in twenty or thirty years and am massively out of practice. So I voted just ‘some idea of the basics’.

For food that does need to be cut with a knife, I cut several pieces at once, then switch hands and eat them. (I’m aware that Miss Manners would probably frown on this, and if I were at a really fancy dinner I probably wouldn’t do it that way. I also wouldn’t have a book in my other hand, but I often eat alone and I usually do.) I haven’t been paying any attention to which way up the tines are and I think I don’t always do it the same way and that it may depend on the food – I think it may be tines-down for meat and tines-up for something like rice or mashed potatoes. Now maybe I’ll notice for a while which one I’m doing; or maybe I won’t.
This is me too.
I guess when I really think about it I do have tines down when I’ve cut a piece of meat using the fork in my left hand and knife in my right and then just bring the pierced piece of meat to my mouth.
I’ve ridden horseback since I was a kid. I’m pretty comfortable riding, assuming the horse isn’t a crazy stallion.

I don’t know enough about the cryptids to answer, and I am unwilling to invest the time to look them all up.
Schrodinger’s cat is just a regular cat. To look after it, take it out of the box as swiftly as possible, before it gets poisoned.