Then they should be a bit smaller. Those are really a good indicator whether the settings are good or a little off. I was searching for ages where my problems were (and it was really simple in the end):
You can see on the very left piece how dogbones should look when everything is working as intended. To be fair: this is the ultimate test, because those boxes and the rapid changes in x and y amplify every little error. „Normal“ cuts normally don‘t suffer from those problems, when using a finishing pass you will never notice because the flex is not a problem then.
Please don‘t take me for an ass, I just know that I was getting really annoyed by it and want to help. 
/edit: I just figured that your box is really tiny, then it is alright. Ignore everything that I said. 