[Replicant]

No, I don't edit core files. I do edit templates though but that is irrelevant since the template is included in the custom styles. Most of the api is available in the templates and via ajax so pretty much anything that needs to be done can be done at template level or dom level via javascript.

EDIT:Currently, if you want to use the new hook system, you do have to edit files, obviously to put the hook where you want it. This won't change until more developers give input to vb dev to identify where they want or need hooks added.