Truly the sloppiest hardcore I know is by a band called Psycho Sin. I got an LP called "Forward to the Caves" which was so inept, it was hard to figure whether it was all on purpose or whether they really were that unmusical. The charisma of the vocals made for good comedy, though. They rewrote "My Country Tis of Thee" into an anti-patriotic song that descends into blur. It's all trying to approximate grindcore circa 1988 (esp. Sore Throat), but it's total hackwork.
My friend Rob says he has the Psycho Sin 7" called "You Axed for It" and that it's far more ridiculous than this LP, though. I gotta hear that someday.
I'd post it here, but the only person that's ever threatened me for putting up an AFS playlist with their music in it was a member of Psycho Sin. He said that the band was back together...but that was about 2-3 years ago, and I've not heard a peep since....other than this notice that their complete discography's on a CD now....
http://speedstaterecords.com/main.htm
Also, T&B...If you have the same taste for ineptitude as I do sometimes, check this list out...
http://www.shit-fi.com/shitlist.html