I believe in some interviews with fenriz and culto (up on youtube) they even talk about how they used a lot of their older death metal riffs on A blaze... that they just slowed down or reshaped a bit, and it's only on UaFM that every riff is full on black metal (as in, i guess, not old DM riffs squeezing into songs) or whathave you. But this is sort of besides the point and doesn't really matter, because for what it is it's hard or near impossible to not call a blaze... 100% bm, but that is a cool bit of info that i found intriguing as a fan and somewhat musical mind.
Personally i don't care if something is 100% this or that, but a bit of musical history can never hurt and is fun to know at the same time.