First, good for them, trying a different way of selling their time. I recall Pirate Radio trying to do something similar back in their early months. It felt like it was actually working for a while. And the NPR model has always been intriguing - using less obtrusive "credits" to generate revenue, but not piss off their listeners. But then there are those "Pledge Drives."
Second, it may be hard to judge the effectiveness this policy has on ratings. This is because their format doesn't have a track record. Had they tried this on their Classic Rock format, we would have had a clear indication of how much this new architecture might drive listenership. With a new format, we may be asking whether it's working because of the music or the commercial policy.
Finally, a few words about Classic Rock. It is ironic that Clear Channel is trying this in place of the former KZPS. Back at the turn of the millennium, this was a very successful Classic Rock station. Programmer John Larson really had the station going, and it did extremely well among both Adults and Men 25-54 - even in a Country music mecca. For the Metroplex to lose its main Classic Rocker is somewhat amazing, given how strong Classic Rock continues to perform in market after market. Today, it is the most successful Rock-based format, featuring more stations than Mainstream/Active, Alternative, and Triple A combined.
Maybe Clear Channel knows something we don't know. Or maybe they don't.