I dont know about everyone else out there, but I have some bad habits. One of them is applying too much much in my EQ when I'm mixing. I do this EVERY time I do a track and then have to go back and hack away at it after the fact. Its really bad.
I used to think it was because I was a bad mixer or because I was trying to make bad mixes etc. The real reason is that I listened to a lot of music when I was younger that had a lot of bass (dance, industrial, death metal etc) so my ears are trained to like certain kinds of EQ decisions (abuse). As such I've developed a good habit recently of placing an EQ on the master channel while I mix that compensates for some of these bad habits by exagurating them. For instance in the image below you can see my basic EQ that I use for this purpose. Its a 3db boost of the bass shelf from about 150, a 3db boost at 400 and then a 3db cut shelf of the hi's from about 10k.
I find that using this method, when I remove the eq afterwards, my mixes hold together a bit better. Then if I need to boost bass slightly when I reference them against other mixes, I have much more space to make that decision.