So you have to find several people you trust, and each one is supposed to hold a part of your backup key or seedphrase?
You can keep the backups yourself.
Even if you trust each of these people, how do you know one or more of them won't accidentally lose it or forget about it and throw it away? Then you are screwed.
Assuming you generate 3 shares for it, you can set it in a way that only 2 is required for the recovery. You can even make it 1 for the recovery but no purpose of having 3 shares in this regard. I just use it to explain.
I haven't heard of this before, sounds similar to mulitsig but then sharing your seed with others in piece?.. well I won't recommend it though.. as a someone who really want to enjoy the freedom of a decentralized system and being your own bank.. it's best to keep your keys your self. I don't see how difficult it is to store your seed offline and in a place where only you will be aware of..
You can keep all the shares yourself. But it can help just like multisig but it is different from multisig.
Reputed members on this forum like gmaxwell does not recommend it.