I like that idea, but it carries a risk of loosing either of them. I have tried many ways to store my seed before and I have found one which still works best for me.
What I use is many random words in a piece of paper. I randomly put my seed in them and list the numbers where they are. Then I take that number individually, randomised it and then turn them into morse code. After that I have painted that morse code on my wall, piece of paper and wood to keep it safe. To a normal person, it will be just dot's and lines. But to me, I know what it is. Also, this will ensure the safety that you can individually back up that word list as well as the morse code to 2 different online platforms. Just make sure to make the word list so big that no one will be able to figure it out. And keeping them in individual platforms as well as hard copy will ensure that you will never lose either of them.

I know making online backup is quite risky. But big word list is quite hard to crack. Imagine putting 500/1000 words in a list. Good luck to the person trying to crack it. Or you can just back up the word list and keep the morse code to yourself. Less to worry about.

I am doing this for a long time and haven't faced any issue. But if you ever want to try it. Do some research on your own.

Or maybe you can used or implement:-> https://iancoleman.io/shamir/

Of course, it might not be perfect as it could have it's flaw. There is also a good discussion here, Ian Coleman BIP39 Derive P2SH addresses from Electrum generated Seed.

Someone must have done all these already. It would be stupid to do it here in the forum though.

Hope no one figures out where he stores it. Because if you have same username on other accounts, you will be traced and someone might just get your coins.
This idea could get people to hunt seed on the internet, its gonna be play time for those internet detectives. Those guys are really good at it, they will be able to find your accounts and find the other seed words.

Giving almost 80% of those private seed phrase then having that someone do aware about that will really be completely risky. Somewhat its really hard to bruteforce or trying out to find that missing 2 words but to know that having that possibility wont really be giving out that kind of confidence on your wallet total security.If you are that someone who do really give out importance about your wallet security then you should really be the only one who would really be having that awareness or do know about those keys or else you would really be putting your funds at great risks.
Its not something that should really be given out something even if you are both siblings or family members or best friends but still when it comes or in talks about money then its a different story.
Store it up on somewhere that it is really that far away on others attention or would really be able to know because once it would be known then say goodbye with your funds.

Not too bad, but remembering the splitted location is really a big issue. Keeping two words memorized is really good and makes it more secure. However we don't know what happens the next minute, and for that reason we're supposed to keep one of our close person informed about the recovery phrase. In such scenario how can that be done. The plan to keep words splitted is good, but there needs to be few backups and locations were entire phrase is kept for the future.

Every idea that have an advantage will also have disadvantage. There's huge risk in split sees phrase not talk about keeping the seed phrase off head which is totally naive of not thinking of the possibility of having dissociative amnesia which could lead to forgetting some important things.
I will suggest he get metal steal that's tested for heat, corrosion, and acid test from Jameson Lopp, get a safety deposit box, and keep it there.

I won't personally do this, but, yeah, it's probably safer this way. If somebody found the 10 of the 12 or 20 of the 24 seed words, they still can't have access to your funds. If somebody found the 2 of 10 or 4 of 24, they also can't lay their hands on your money. But this also poses certain risks. What if you can't find all of them? What if you forget the sequence of those words?

But I guess it's pretty much manageable this way rather than make a puzzle out of your backup. I also think having more than 2 copies of each is better.

Writing the seed phrase down in one place is a good idea and it will help you in the future when you misplace your phone or system that contain your seeds phrase, and you will be easily go back to those seeds phrase you write down to restore your money back.  I don't think, I will advise anyone to divide their seeds phrase and write them in a separate places, which is not a good idea because it will be easy for such person to regret when he or she can't remember where the 2 seed phrase are in the house. Many people do all those things by writing the seed phrase for different places for past experiences purpose, because if your wife or children know Bitcoin and wallet very well, very easy for them to know seeds phrase of any wallets, and it will be easy for them to know how much their father has in his wallet.

It's a good security method as long as you always remember the complexity. But there is no need to do this if you have adhered to the standard method of protecting and keeping your wallet safe. This technique could breed carelessness because you know that the seed phrase is complex. I am also concerned with transferring my coins to my next of kin in case of an emergency. Sickness and death are unpredictable, hence there is a need to make your wallet less complex so that your dependents can have access to them without much restriction. I am just considering how my next of kin will be able to have access to my wallet with all these complexities of removing words because it took long lectures for them to even understand the simple wallet security tips. A little confusion can make the coin to be lost forever.