I've never seen anyone else do that, but it certainly worked. Though I remember wondering why not rotate it the other way, so 'down' becomes left and hand wouldn't pass over the previous line either.
However, I guess the problem is that it basically means you have to learn writing the letters in a completely different way and most 6 year olds will not be able to come up with that themselves.
Edit:
> Left-to-right alphabets can be written smudge-free and in proper "forward slant" with the left hand if the paper is turned 1⁄4 turn clockwise (90 degrees to the right), and the left hand is drawn toward the body on forward strokes, and left to right on upward strokes (as expressed in directionality of the text). It is also possible to do calligraphy in this posture with the left hand, but using right-handed pen nibs.
https://en.m.wikipedia.org/wiki/Bias_against_left-handed_peo...
I, although also left-handed, never wrote like that, I did the "wrist-bending" instead.
Edit: this also makes me wonder how the hell Ben Yehuda revived Hebrew without ballpoint pens.
As a left handed person, I'd recommend you give it a go for a few months, I think you'll find it a good bit harder than you might think - although you're probably not handwriting pages of text all day anymore, so whether it's a fair comparison I don't know.
I certainly found it quite tortuous to be forced to do things with my less (forgive the pun) dextrous hand: it takes constant conscious effort, like a wasteful background process. And that's not to mention the psychological effect of, as a child, being scolded because the most comfortable & natural way of doing something is "wrong".
Edit: Wikipedia has an interesting section on other consequences of forced conversion: https://en.wikipedia.org/wiki/Bias_against_left-handed_peopl...
> Although it is hard to pinpoint why Arabic is sinistroverse, it has been theorized that before the papermaking process emerged in China, the Arabs used chisels to engrave the ideas and concepts they wished to manifest on stones. Due to its longevity, stone was preferred over leaves, skin, bones and shells. Considering most of the “writers” [and individuals in general] were right-handed, they would use their right hand to hold [and carve with] the chisel and the left hand to hold a hammer. Such direction is more natural because it involves an outward motion and is, therefore, easier to perform from a motor point of view. A left-to-right motion would have been counterintuitive, especially with the risk of personal injury involved.[1]
However, as another comment mentioned there are techniques that solve the smearing and awkward hand-position by rotating the paper. I would not be surprised if those are taught more widely for Arabic as 90% instead of 10% of writers face that problem.
[1] https://www.pangeanic.com/knowledge_center/arabic-right-to-l...
So any hypothesis about the origin of the right-to-left direction must discuss only how the tools were used for the Egyptian hieratic (written with brushes) and hieroglyphic (carved with chisels) writing systems.
Maybe it was easier to carve hieroglyphs in that direction, but I am not aware of anyone testing this hypothesis in practice.
If you hold the hammer in the right and the chisel in the left, you swing the hammer from the right to the left with the chisel tilted to the right. Thus the natural writing direction (outward from the swing) would be right to left. Swinging your hammer from the right and moving to the left would mean writing in the opposite direction of the force used to write single letters.
So, if the hammer is in the right hand and chisel in the left means a right-to-left motion and makes a left-to-right motion counterintuitive.
Think of it as a nail: if you need to hammer in a nail in exactly the right place, you put the nail into exact position holding it with a left hand, then strike it with force using hammer in the right hand. And if you ever did this you know that the tricky part is hitting the nail the right way, so you don't bend it.
We were also forced to use it in German elementary school and I remember very well that my dad went to the dean (successfully) demanding that I am allowed to write with something else and abandon cursive training. Thanks again dad!