[Catalyst] Login authentication using C::HTML::FormBuilder ...

I'm using C::HTML::FormBuilder for a simple login form and would like to
use the standard $c->authenticate() for validation.

This means that I either have to pass ctx => $c to
$form->process(), more tightly coupling the controller to the form,
or do all of the $c->authenticate() stuff after $form->validated(),
making my controller fatter.

Is there another way of accomplishing this more elegantly, or is one of
these options acceptable?

Just curious is all.