I don't know anything about the author in question, but one possibility of the fics are spaced out in time is that you're seeing her older and newer work next to each other. I know I can't bear to look at some of my original and fan stories from even a year or two ago, let alone some of my very early stuff.
I'd say that regardless of what you think of her 'good' stuff, it's still fine to say that the 'bad' stuff is indeed bad as long as it meets the negative standard for being counted as bad.

Did I just hear "Debt"? I only read one chapter of that and could go no farther.

I've only read one other fic from the author (which was also disturbing in a different way, and also has a TV Tropes page), so I'm not sure about the quality of most of her fics. However, I would not base quality of a fic on the general quality an author has. Some improve over time and write very well at present time but have some downright terrible fics from when they first started. (I suffered from this, for example.)

Tl;dr- Badfics should be looked at on an individual basis, not necessarily looking at an author's entire work (though often badfics's authors will write other badfics). Does that make any sense?

...in general, if the gore is completely out of character for not only the characters but for the world as a whole, and if when you seperate out the gore, the plot itself is bad, or has more plot holes than an art film, then yes, you could legitimately spork the thing (see Cupcakes for a particularly infamous example).