I am breaking all the diversification rules right now by keeping almost 90% of my money in AIG. I used to hold ARR or AGNC, but I have switched to AIG in Sept 2012.
Portfolio contents at 12/31/2013
AIG (92%) BAC(4%) BRK.B(2%), AGNC (2%) ARR(1.5%)
I am a systems, rules based, long term trader & teacher. I go out of my way to avoid noise, while managing risk. I view the market via WEEKLY bars. A careful examination of my list of losing and winning trades tells the complete story.