[fel64]

In principle it’s possible to do so by replacing all the template functions with custom functions that call a custom filter first, but it probably wouldn’t work out overall (not everyone would do it, plugins would still have to be written for forums without this, changes to the core would have to be replicated …).

Probably better to say that not all functions have _hooks_ or _filters_, since pluggable refers to them being overwritable with another function (see bb-includes/pluggable.php).

You could request this in trac I suppose. Might be quite a decent feature in the future.