Rumour has it

[Dextrimental]

Machine Head apologised for not headlining the US with the Blackening, apparently because they were being offered awesome support slots and they felt they had to kind of work on their standing in the US, so they could do a tour over there that was as big, if not bigger, than the European tours they've been doing, Black Crusade and Black Procession etc.

And if that tour was true, High on Fire would be bottom of my list. But thats not to say I dont like them, I merely prefer Testament, Megadeth and Slayer, I hold all four bands in very high regard.