The anime can make a decent job at fillers if they really want to put effort into it. They've made arcs that I considered as high grade ones such as the Three-Tails and Utakata arcs.
The problem is, when they screw up the results are outright awful as well. They usually don't bother with a story line for the filler arcs anymore and prefer to go for the one-shot episodes formula, the result is often non-sense stuff like ninja ostriches and sumo fighters attempting a village takeover or Naruto in our usual butt monkey episode. Recently the writters became more lazy in regarding expanding fight scenes as well, they abuse flashbacks for padding and often don't even care about consistency or the material they are going to use to increase the length of the fight. And I'm not only talking about Super-Kiba and Shikamaru's earplugs, who here doesn't remember Looney Tunes over the sea after all?
It came to the point it is difficulty to believe it is from the same people that made the Utakata arc, but I still have hope because they've done nice works before and I always look forward to watch something from the same level. Recently the quality has begun to grow a little again with the Swordsmen fights, it is not what it used to be but is a start. They are doing some good jobs and some bad ones. The last episode with the Sound Four could've been done way better, but was below expectations, while the Chikara arc was exceptional.
In other words, it varies. They can do good fillers if they really want it, but that doesn't always happens.
