Horcruxes provide a unique solution to the problem of dragnets and increase costs of hacking your device even for governments.
https://wikileaks.org/ciav7p1/cms/files/NOD%20Cryptographic%...
> Certificate validation must not be performed against any standard SSL root CAs.
> implement an inner cryptostream within the SSL tunnel transfer
People often state that you should not roll your own crypto. Definitely, you look foolish for making a mistake doing your own thing. However, adding your own layer on top of a standard one seems safe and likely to slow an adversary down considerably. Adding a layer below to encrypt data before the standard algorithm gets it has some risks (e.g. could leak in some complex way like a timing attack) but it also protects against a compromise in the implementation of the standard algorithm.
Adding the Horcrux layer of multiple channels does seem to increase security at the cost of creating a new unvalidated magic wand that then becomes the attack surface - and another significant cost in that it is not user friendly and involves considerable effort per message. There are ways of implementing greater security at high cost, e.g. point-to-point communications off network. The question is if the extra effort confers any benefit. Sometimes just the fact that two parties are communicating is valuable knowledge and this Horcrux mechanism actually makes that easier to detect as it occurs across multiple systems.
> Sometimes just the fact that two parties are communicating is valuable knowledge and this Horcrux mechanism actually makes that easier to detect as it occurs across multiple systems.
Steganography can alleviate that red flag.
Sure, but the problem it solves is not the problem that needs addressing. Ciphertext and key delivery can already be done safely with E2EE apps like Signal. Metadata can be eliminated with e.g. Tor Onion Services.
Your apps relies on QR-codes to exchange data, the same channel can be used to authenticate Signal endpoints and/or exchange PSKs, no need for SSS. Goal for information theoretic security is fine but considering nobody is doing CT-only attacks against modern algorithms anyway, the easiest attack vector will be MITM attack or remote key exfiltration. E.g. Snowden has been very vocal in the past about NSAs of the world hacking endpoints, but has quieted a bit down wrt the matter, perhaps he realized that was too high bar for average users who still benefit from incremental security from Signal etc.