getSimpleCacheData availability in templates

Is XenForo_Application::getSimpleCacheData available from PAGE_CONTAINER only?

If so, is there a similar approach to access cache data from templates (or template modifications), e.g. forum_list?
PHP isn't available via templates.
What I meant to say is params written to the cache (by a cron job say) is accessible in PAGE_CONTAINER, e.g. via {$someParam}. But the same {$someParam} is not working outside of the PAGE_CONTAINER template, e.g. in forum_list.

Maybe I am missing something, but I couldn't get it to work.