All of you will be alerted and asked to report me about undesired behaviours, I expect your collaboration ;-)
Here we go: Varnish is actually in action.
Connections from authenticated users are passed to the backend, but all traffic from occasional users (e.g. people landing to the forum from Google) are managed by the cache.
If you encounter problems, errors, unexpected behaviours and so on, drop me a line in this thread or via email@example.com
Thanks for support and further suggestions.