freitasm: Not exactly. There are things that should be correctly configured. For example a non-Telecom handset, even though they might have the right bands could have the wrong dormancy settings.
If wrongly set these will cause excessive battery usage, frequent disconnections, slow response, etc.
Why not just have a 'carrier pack' like Apple does then? And then the carrier can just push out tweaks rather than having it tied to the entire OS build. Or separate the layers. It's like saying your ISP has to approve the next version of your browser or something like that