What Nirvana released with Bleach didn't really kick start or shape anything. Bands like Mudhoney were releasing material similar in style yet superior and more culturally significant to this at the time. Superfuzz Bigmuff is a case in point, that EP helped mobilise the Seattle scene, with the Deep Six compilation and early Green River EPs moulding the grunge movement even before that.

The Melvins released Guey Porch treatments in '87 and Ozma in 89'. Nirvana were clearly influenced by these releases, but both were better than Bleach. The fact it sounds like them means shit all.

Nirvana only really became significant with Nevermind. Bleach has gone on to become Sub Pop's biggest seller, but only really because of the legacy forged through the band's later releases.

wel, if Nirvana didn't get that much exposure, lots of people wouldn't have heard the Melvins

Did he say so in an interview? I kinda doubt this.

Nirvana obviously gained masses of exposure, following the release of Nevermind. The album's success made Cobain the poster boy and gave him a voice yada yada. The fact he often referred to the Melvins as a key influence went a long way in raising the Melvins' popularity.

I am sure Kurt would have completely agreed with you on this.

He did once mention he worte lyrics on the way to the studio in the car, was for Never mind or in utero though,can't recall the song. It is mentioned in the book "come as you are" by michael azerrad.

Invented an attitude that was extremely common in 80s underground?

not really a "trademark" then

I wouldn't call it underrated. Its a decent rock album though, maybe a bit too repetitive.

Paper Cuts is definitely my favorite track, its so dark and heavy and the lyrics really drag you "down".

I was watching an interview with Ian Astbury lead vocalist for the band The Cult, and Astbury stated that the album Bleach by Nirvana was the first major album that signaled something new and different was at hand, concerning the grunge era and the popularity and sound of all prior rock music of the 80s and 90s (at the time of its release). So the album Bleach seems very significant (to me) as being the first popular album to bring grunge music to the mainstream.

That is my conclusion and opinion, to the statistical significance of the album anyway.