Album for Album

Hmmmmm

I'd say...

Dark Tranquility
**Puts on Flame suit** (InFlames) I loved all their CD's really, and they have progressed so much, for some better for some not, but they are consistent, and creative.

Oh noes another flame suit (Children of Bodom) - They have been around for a while now, and still putting out good shit, but, the main reason they are here, is because they basically started the keyboard centered melodic death movement. I know alot of you hate it, but you can't deny it.
 
This is a touch choice for me, as many of the bands I like haven't been around long enough to qualify. I'll say Carcass, because they did well with a few different styles and released some genre defining albums.
 
If the next Drudkh album is up to the standards of the rest of their catalogue, then you have to consider them.

I can think of lots of bands that are just one release short. Carcass, if not for Swansong. Opeth, if not for Deliverance. Deathspell Omega, if not for Infernal Battles.

Just about all of Xasthur's releases are in the 8/10 range.
 
there's no point in arguing whether X song or X band is heavier than the other as people don't even have a vaguely similar concept of the word "heavy"

"heaviness" is pretty much entirely subjective
 
Actually there was a gigantic thread a while back where everyone agreed (though in many different ways :p) that heaviness is subjective. I doubt your reasoning is unique!