You doubt?
As for the Edguy, Therion and Epica tours floundering, they really need another headliner. Especially Therion and Epica. They just aren't well known enought to draw by themselves. Also, everyone coming over during the same time can definitely be a factor. I have so many shows at this time, I can hardly keep track of them all. I was scheduled for 4 last week, but only made 2. I surely would love to see more in January, March and April; typical dead months. Screw the cold weather. We need more metal.
I think these factors are a major point. I mostly go to shows in Worcester/Poughkeepsie/Albany, and the bands that go it alone (genrewise) usually suffer the most. The Palladium and the Chance can go from 100 or so (at best) for Therion, Edguy, Helloween, when those bands are the only similar draw, to several hundred when it's Hammerfall/Edguy, Kamelot/Epica, Manowar/Rhapsody.
The other point being all the "same" type of bands touring at the same time is probably a big thing too. I am in an area that w/in a 3 hour drive I can hit most tours, and it seems that all the "obscure" bands tour at the same time. This year, w/in a couple of months I get Sym X, SA, Edguy and Kamelot. The prior nine months it was bands that have been around forever: LA Guns, Nugent, H&H, Tesla, Queensryche, etc. I want to support the newer bands, but damn 3, 4 or 5 concerts in a month (w/ shirts) is a lot of $$. I AM still going to every show though irregardless, love my metal!!!
Of course, it's tough for different bands to know when another band w/ a similar fanbase will be on tour too, but i'm sure it hurts sales if you have to choose. The biggest thing though is touring w/ bands that have nothing in common w/ your band. I'm sure a lot of it is label directed, and there is something to be said for bringing in a diverse audience, but It seems that having at least two bands that have the same crowd for this music helps since bands have to rely on travellers from a wider geographic area, due to the smaller amount of dates.
j/k bro. If the show is in Sayerville or whatever, I'll pick you up. 
