Code review comment for lp:~jelmer/bzr/lazy-registries

> If we add a new class, then that means that any users of registries would
> either have to stick with the old implementation *or* be converted to the
> new one.

Hmm. That's true.

On the other hand it means we will never have a clean cut nor a clean
implementation because plugins have no incentive to use the new one, no
deprecation warning here, no nothing.

Not worth blocking this one but I'm always a bit worried when we add more
cruft without a clear path to get rid of it :-/