Memorizing isn't that hard or bad practice.
Only if you also have physical back ups. Relying only on your memory is very bad practice.
Be frank, aren't there some long poems that you learned so well in school that you still remember them word by word?
If yes, then I hope you got my point.
And if you get into crash or get a heart attack, develop dementia or something terrible happens, the first question is if you survive and the second question is, if you actually remember that you have bitcoins or in best case, where you saved your seeds.
You are more likely to remember where you physically put something than a list of words you just repeat to yourself over and over. And if you forget the location of your back up, you can at least look for it. If you forget your memorized seed phrase, your coins are gone.
-snip-
By the way, if you try to memorize 18 or 24 words, then you shouldn't trust your mind in this case because it's too much to properly remember for a long period of time. 12 words are fine!
12 words will also not be fine and you should not trust your mind completely. The human brain is indeed capable of remembering anything in the long run if it is trained, but the human brain also has an age. As we get older or enter the aging period the brain's ability will decrease slightly.
Senile dementia will be a problem if you have to remember 12 words without any copies.
If I am an old man with not so good memory, I wouldn't trust myself. Finally, everything comes down to what you are capable to handle. But guys, if you say that if you get stroke or heart attack or dementia or crush accident or fell from the mountain, etc, then I have a question, what makes you confident in remembering the secret place where you stored your keys? Let's be frank, in such extreme cases, our methods don't have any advantage. If you save your seeds in a place that's easy to reach for everyone, then you are not actually keeping your seeds safe and if you save it in a secret place that's hard to find for anyone and you experience extremely bad accident, then more likely you won't be able to recall that place and in extreme cases, you won't be able to even acknowledge that you had something saved. This applies to memorizing, if one is fucked, doesn't matter he/she memorizes or saves it in a secret safe place, the person is in trouble.
So, once again, I want to say that
everything comes with a price!