So I've seen this pop up on the D3 general forums before and I've been thinking about it a bit lately. I figured why not ask the people with the most experience in seeing items drops.
After 3 months of multiple bots I can all but confirm this is true (for me anyway). I run both barbs and monks and I always find the godly items on the opposite class. Finally this morning my Plvl100 barb bot found it's first IK Chest (which prompted my thoughts on this). Between my monks I've probably found 15 or so throughout their life. And this trend is true for almost all the "good" legendaries.
To add, I've been thinking about starting a Wizard for my next bot just for testing purposes. Also, the fact that between all my bots I've found some seriously sick Wiz/WD gear (perfect Witching Hour, near perfect Chantodo's, etc...) really makes me wonder what kind of gear I can find for the other classes.
So what are everyone's thoughts?
TL;DR - I find tons of barb gear on my monks and vice versa.