Sorry, but what is that supposed to mean?

The functionality on either end of a client/server application is usually not "mutually exclusive". They're two sides of the same coin and could indeed benefit tremendously from code sharing. Just because the potential has barely been realized so far doesn't mean it doesn't exist.

Math (significant math), encoding and hashing being done on the client sounds like a poorly designed application. Same for templating on the server -- which I assume you mean manually compiling templates using a library, and sending the result to a client, perhaps as a property of a JSON object.

Also I appreciate you picking up where I left off, I've been making a major lifestyle change and am almost completely sapped of energy.

This has improved my concision considerably wrt code and conversation.

Cheers, let me know if you find yourself in SF, I'll get you a round on me.