@antohan Even Abidal for Barcelona moved forward and provided width at times with Alves on the other side. The formation you have created is how the team will look when I attack through the left side - which with Brehme being the best offensive threat - will be the manner my team will be prone to attack.
When the team moves up through the right the team will use Zanetti's width which is world-class as well, the same way Barcelona allowed Abidal to also move forward - even if Alves was better offensively. There is a reason 99% of sides uses both full-backs alternating with pushing forward - there is also a reason why all teams has a side they are more prone to attacking through as it is a better attacking set up.
With Brehme being better at finding space offensively and getting involved the team is going to attack there more than at Zanetti's side.
I've never seen a non Catenaccio team use the tactics you describe of having a full-back who never moves forward. Even United last season with Evra and Smalling in the side, saw Smalling move forward plenty as well.
The difference between adding Conti as an attacker and adding him here in his better role IMO as a right winger is how they work defensively. Conti can in the offense move about as he wishes anyhow, but has a defensive job out right.
Enrique's role on the left is similar, he is always prone to cutting inside and his defensive role is what makes it a 4-4-1-1 defensively. In the offense he will be doing the balance job which I think is needed here.
If Effenberg pushes forward for example Enrique will be doing the job to cover and he is comfortable as a combative CM as well so it comes in handy.