Re-doing one of my hacks tonight, I find I can do it the standard way - with file edits - or - if I start duplicating blocks of already run code, and a few other messy tricks (like duplicating an already run query, and altering GPC variables) I can actually make it work with just hooks.
Now the question is - which is better - nice simple code that requires the end user to edit vb files, or messy, fudged, repeating code that simply requires the end user to upload a set of plugins.
An interesting problem ........
I think at the end of the day you have to ask yourself what is best for the server. If there is no big differnce between a hack and a hook in speed and load I'd make it a hook for the pubilc, but I would still probbly hack it in for my own board depending on what it is.