I understood fully how you arrived at the 11% yield. I used an algebraic formula using X as your cost.
My point is that if you own 1000 shares you now have $39000 worth of value and your return on that value is 2.8 or 2.9%. $1000 per year @ 25 cents per share..
I'm not saying that you should sell DOW. I did do some comparisons...if you sold DOW and put the $39000 in another stock, your annual income would increase significantly. For example: With $39000 you could buy 2167 shares of CNP and your annual dividend would be $1712. Or you could buy 2805 shares of FNFG and your annual dividend would be $1795.
Extrapolate those numbers over 20 years and check the return on your original investment.
BTW, I really think DOW will return to a $2 per share dividend or higher sometime within the next 3 to 5 years. But DOW has historically been very cyclical.
I look at it like you do. cost average never increases unless you buy more and average up ... and by the way show me a bank that is paying over 3% right now, the Dow I own will sit till I retire I'm happy with my 6.6% in these kind of times and when they increase the dividend my 6.6 will go up, I don't like to day trade.