Interesting.  Bytes in/out?  Getting HTTP header overhead?  Accurate timing? If you say yes then I'll gladly look into it, I'd be happy to reduce the surface area.

RE: guaranteed to work and missing something.  I have provided the beginnings of a test suite that _should_ (famous last words ;-) ) reduce the likelihood of missing something (I've even included a preliminary "happens before" relationship map that would need to be adhered to).

RE: Breaking stuff.  Well, sometimes we're going to break stuff.  The tests should help us understand what we've broken (regardless of underlying implementation).  It is preferable to be explicit about what is going to break.  Hopefully, the basics will hold together for a reasonable amount of time.