Yep, I go with T1m on this - most of the online games you play are probably connecting to a dedicated server, but due to the two player game that BLIC is it makes far more sense to operate on a peer to peer basis. That's a very different set up with no middleman involved.
The problem that these instructions resolve is being caused by your router and/or firewalls security measures, not by anything Codemasters have done or failed to have done (I can't see how it'd be feasible to make this an automated process)