Pig, for me its all in the context of ones portfolio and needs. My caveat is I have a pension I live on. If it was cut 20% today, it would still cover all my needs (but I wouldnt get to buy new money preferreds nearly as often, lol).
Cap's style is more fundamentally sounder than mine. I have probably over 35% of my money just in Ameren preferreds and basically all of my investment money (not my savings account and gambling stash, lol) is in preferreds. So I am violating 3 financial golden rules already... Class concentration (preferreds), sector concentration (utilities), and company specific concentration.
I dont give a rats arse either... I am sticking to what I am comfortable with. Hell, my 87 year old neighbor for 60 years plus has only had CDs and Union Electric (now Ameren) and that is it. Worked out well for him.
But I own mostly old preferreds that I have tracked through time. I know exactly where they will trade at various rate intervals after the few days of panic settle down. Heck AILLL was issued at par 6.625% when the 10 year was 4.5%. I would be extremely surprised if it traded below par for any extended period of time until 10 year approached 4%. ....And if it did I would sell my other stuff and buy even more, lol.. BTW, I consider this portfolio diversification, as I damn well know my pension manager has none of the stuff I own. But I am a pensioner, not an aristocrat, so my pension is way more important to me long term than my personal money is....If I want to live a long life and not have to work, lol.