Dollar Cost Averaging in a Flat Market

I read in a blog that if one were to buy into the stock market in 2000, he would still be losing money by the end of 2011. It is not difficult to tell that from the chart below.


Chart from Yahoo! Finance

Then I read a comment on the same blog saying that that is not a fair statement because in investing, one has got to take into consideration the effect of Dollar Cost Averaging. Intrigued, I downloaded the historical data for SPY and verify it for myself.

Condition:
Start Date: 1 Jun 2000, SPY at: $145.28
End Date: 1 Dec 2011, SPY at: $125.50

Buy $500 worth of SPY monthly from 1 Jun 2000 to 1 Dec 2011.

Result: 
On 1 Dec 2011, we would have spent $61,113.37 buying SPY. The market value of the SPY that we are holding is $66,766. We are sitting on a profit of $5,652.63 which is 8%.

Well, the commenter is right. we will not lose money if we have done Dollar Cost Averaging. But the profit is not impressive. I mean, 8% for 11 years! Not to forget that I did not include the transaction fees and dividend payout (if any) in my calculations.