Ahh okay I see what this is. Well, so long as only the sender and recipient can read the messages, thanks to encryption, then it should follow that not even the servers can hold any relevant data as to what is being said back and forth, other than the fact that two people are using encryption. For example, I'm using Jitsi with encryption right now, with gtalk, and though my messages are stored on google's servers, they're stored like this:
?OTR: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.
I have no idea if someone can figure out what that says but hopefully not. But anyway, the only difference, it seems, between Hemlis and the popular
WhatsApp is who's running the show. So you still have to trust TPB guys that they'll remain angels forever, which I suppose can be seen as an improvement over WhatsApp inc (who lacks the history TPB has), but it's still basically a rehash of the same thing.
I guess I'll try it out anyway, whenever it's available. It certainly looks appealing.