It tries to hard. And it just fails.
Honestly, this "tough toph" is two things:
a) Weaker than the canon one. (she can't bend sand or truly see with vibration, like Toph demonstrated in the Phoenix King)
B) A parody of the badass action girl.
And I don't mean an direct parody of the Action girl, like other reviewers are implying. It's like seeing a 12 year old girl trying to be a cold hardass and failing at it, which is ironic since the actual
12 year old was a fascinating amalgamation of a great warrior, a genius and a scared, insecure high born girl. This is just a jackass who try to hard to impress the audience.
Just from the title you know that it's a silly fic. It's not a deconstruction of Fan Wank in the same way that crank is not a deconstruction of action films. It's not even a take that of the Fanon wank since it doesn't use the obvious reasons why toph is so adored (she is strong but not a bully, independient but still in need of others, a genius who can still grow and so on), it doesn't explain its reason well beside a generic backstory and the context is almost offensively badly implemented.
This Toph is offensive, it's rude and just plain unlikable. It's not a bad fic, but a bland one and that just make it worse.
The Full Metal Bitch... showing that Toph, in fact, can't make everything awesome.