I like the idea of w3tc_do_action('w3tc_pgcache_cache_key,...) but definitely that would be helpful if you could add some more hooks.
Especially in these methods:
- add/replace/delete in W3/Cache/File.php
- _can_cache() in W3/PgCache.php
I am using W3 total cache within a blog, that has such features as:
- custom post permalinks (modified for some posts)
- custom subdomains per category (e.g., categoryA.domain.com mapped to domain.com/category/categoryA)
Sometimes when I want page cache get cleared, another related pages' cache has to be cleared too.
So I would see here some kind of action hook/filter that would allow me to clear that other pages.