Bain Capital and THL Partners had to sue six banks to get them to finance the deal to take over Clear Channel Communications, the nation's largest radio-station operator, a deal that was first agreed to in 2007. In the interim, the sky fell, and so did radio advertising revenues. Although Bain/THL eventually made the deal at $36 a share $3.20 less than their original offer music coming out of the radio business these days is anything but sweet. And the more than $17 billion in debt taken on to complete the deal has got to be feeling very, very heavy.