I think the bottom line of teaching techniques to beginner skill levels is reducing mistakes that lead to injury/damage.
For example:
Washing out the front: this is often caused by steering the front wheel a bit too much, with too much momentum wanting to go in the original direction and disagreeing with the direction the front wheel is wanting to go in. Some refer to it as the front wheel being pushed.
One basic counter-measure I developed is to simply remind yourself that your body needing to make the direction change is different from the bike needing to make the direction change. The bike is connected to the ground and the rider is connected to the bike. You need to plan accordingly, based on what's upcoming on the trail. Sometimes, you don't need to change the direction of the body that much, since the trail immediately zig-zags back. Technically, the body might not even ever need to change direction, like in a chicane. You can basically make your bike take the twists alone, while the body goes sideways to stay connected to the bike, with the core of your body hovering over the apex and the bike being sped up to whip back under to catch the falling body.
On a wide and long carving turn, like on most open paths (like roads), you generally need to work on the optimal alignment angles between you and the trail, for whatever speed you're going at. This is trained up in a parking lot, even a dirt and gravel one, and relies on subconscious muscle memory. The more experience you got, the more data the muscle memory has to work off of to pick an optimal technique for whatever circumstances you enter. I rarely make any conscious decision, unless I'm experimenting. I just crouch and pick a speed that I know I can pull off, and the muscle memory pulls it off. Those videos don't say it, but they're probably just encouraging you to get such experience through targeted training. I guarantee that you won't look anything like the demonstration, since your circumstances will be different and your body is convinced that it has a better adaptation figured out from experience. You basically have to break the body's programming if you think it's wrong and want to switch to a less intuitive one, with forceful conscious adaptation.
A lot of the techniques I pointed out in my first post on this thread counters the washing-out-the-front issue. This is a case of skipping a lot of unnecessary trial and error experience. Getting butt jutted out, crouching low to take advantage of space created by saddle slammed as low as poss, pushing/rolling front wheel in direction I want to go... this last one still incorporates steering, so it might come as a surprise to those who think steering is the issue. It works since the body is primed to change direction, rather than acting like a sack of potatoes, and the bike is already on the correct course and acts as an extra compelling force to change the body's direction (pulls the body into that direction, with minimal risk of wash-out). You need every thing you can get to help change the body's direction, especially if the ground lacks lateral support, and I find this is a relatively safe technique to add to the mix to make sharper turns. Leaning by itself often goes wide, hence why I added this to re-enable steering into the mix and improve the accuracy/precision of staying on whatever line I envisioned taking (proved possible/realistic through experience). It's hard to explain, but I believe steering sort of modulates the amount of lean. My habit of making my body cut the inside, and let the bike swing wide, tends to make the lean a bit excessive, so turning the handlebars more to the inside raises it up, leaving my feet/legs to act as suspension. A pre-requisite to this technique is to not put much weight on the bars, leaving the arms loose/free to use for control.
Also, fair reminder: overthinking things can set you back as much as not thinking enough. Trust in the basics and come up with some confidence to break past your fears, excuses, etc. that prevent you from exploring outside your comfort zone. You learn more from mistakes and shame, IMO. Don't hide from such mistakes; get them out of your system sooner, so you can progress faster. The only pride you should take advantage of is the kind that says you can do whatever someone else can do, like Chris Kovarik's high speed drifting; don't let it talk you into believing that you're already at a higher level than most and fight any attempt to destabilize that belief, that makes it seem as if there's actually a long way to go to actually being called good. I'm still learning lots and not trying to tout/imply that I'm an expert--I'm just practicing trying to explain things to test my own understanding. I was hitting turns faster on my commute the other day to see if I even do what I was preaching... also, I sort of advanced to the straight-lining and jumping phase where I skip over unnecessary curves (I don't follow the other tire tracks on trails around corners anymore, convinced that they're newbie trap lines), ever since I got comfortable on the emtb, so I practice this stuff even less. XD