As author of several "QoT sucks!"-threads I finally discovered a way to win with her.
BUT: Your team partners will think you suck and they won despite you. And the opponents you won against will think you suck, too, and wonder why they lost even though you were on the opposing team.
And that's because you're harmless. You die quick, you don't kill much, you're nearly always running from a fight. And suddenly the enemy citadel collapses. Or the last fortress crumbles.
QoT is probably the only demigod that has no assassination build ... but she has the highest number of builds that will suck.
Anyway, I had to brag that the theory I tested actually works and that playing QoT in a Siege/Support role is both effective and an interesting change of pace (check here for a build guide). You can even use Uproot to great effect.
"Proof" from a Nightmare Tournament:

As you can see from the statistics, QoT sucks.
However, the statistics don't mention that among the 7 destroyed buildings were 4 of 5 fortresses in that fortress game.
Give her a try but be warned: You'll never rule the battlefield and it takes a big effort to avoid ingrained hunter/killer tactics and go for the buildings instead. 