So it would the enforce an '{{action}}.{{type}}' notation (i.e. 'create.success')? I ask because otherwise, some people will set a template at level 1 nesting (i.e. 'success') while other at level 3 (i.e. 'create.user.success') - and having to account for these cases without using Hash will create a very similar overhead IMO but I might totally be wrong.

After your comment earlier on today, I thought if there was any real advantages to using a nested  structure for templates and I couldn't think of any. Maybe just drop nesting all together? What do you think?