The bottom line is this: Just like with PP, European bands often play an earlier slot to secure travel plans. Just because Chris C gets a "headline" position doesn't mean that he will be regarded as the "headliner" by attendees. Like some have said, it's 1 name. I've seen Dark Tranquility listed too and that's fucking awesome. Throw in the Soilwork, Hypocrisy, and Mnemic tour mates and you have 1 night signed sealed and delivered.
Another point: BWBK announced Pete Way acoustic a couple of years ago and everyone's like "Pete Way, WTF???". He kicked ass. He was available to talk, he signed, he performed very well. It was a blast. Same with Crimson Glory this past year. To me, these "left field" choices often enhance the idea because Glen brings all the heavy hitters and both parties have said that they want to keep the competition factor down. Therefore, it's the perfect counterpart to PP.
Finally: Last years card was weak? Primal Fear, Brainstorm, Grave Digger, Elegy, Doro, Metal Church, Flotsam and Jetsam, Lilitu.....weak? Look, you may not be a german metal fan, but just to get Brainstorm and Grave Digger to debut in the USA was a coup IMO. Give some respect for that at least. Last Year's PP was a lot of repeats, albeit good repeats. I think BWBK gave us something totally different and they delivered even if tix were not up to par. Put PP with BWBK and add Chicago now and we're living the good life here (finally) and there are a lot of people who don't see the forest for the trees. Wake up before you miss it.