Yes a few people suggested that. Note that I am maintaining ZERO infrastructure here (important! also since it can help prevent DOS!), so it doesn't cost me an

Yes a few people suggested that. Note that I am maintaining ZERO infrastructure here (important! also since it can help prevent DOS!), so it doesn't cost me anything to send these. A lot of these messaging infrastructures are free to users too. So does it really matter that it's O(h * n)? h will always be not that big too, (n as well!) so it's not that much data. It is not much data, and costs me nothing, and costs the user nothing. Does it matter? I like that OTP has perfect secrecy and is super easy to code and audit the code (NSA hasn't snuck in any weird matrices, no weird goto return bug, buying a bigger quantum computer doesn't break it, etc). You could also use Horcruxes to set up public key encryption or a key exchange, then do the rest of the communication on a new channel directly using public key encryption.