I can relate to this experience, i have a friend who thought writing one word out of his seed phrase was a good way to protect it if someone found the seed phrase, but it is only good until you yourself forget correctly what the last word is, and lock yourself out of your funds. What my friend did was that he would write 12 words down, but one is incorrect, then he would try to memorize the correct word that was omitted, and that which is incorrectly included, so whenever he wants to import his wallet, he would eliminate the incorrect word and replcace it with the correct word he had in his memory, at the time i thought this was a good thing to do.

After close to a year, my friend couldn't remember the correct word he committed to his memory, it was surprising and i can even call it a traumatic experience for him because he kept trying and thinking, he was successful in less that 24 hours though, but it was a risky event, imagine if one can forget just one word, what about 12 words. Memorising seed phrases or trying to be too clever while backing it up is so risky, just do the simple things and have more than one backup.