Unfortunately, I could be described as young (late 20's - early 30's), but hardly inexperienced, just nothing at the majors (to use a bad baseball metaphor), or in other words, nothing at the national or state level.  That said, I had two thoughts.

First, Mike McCurry and Joe Klein aren't exactly the gurus of political thought.  The fact is that the DC group of Dems haven't won anything in over 20 years.  Clinton's victories in 1992 and 1996 were the result of newcomers/outsiders -- Carville, et al. Klein has never run a campaign, and McCurry was either on a losing campaign, or too low on the totem pole to really make a difference.  In other words, McCurry isn't an adult, Carville (along with guys like Bob Muholland) are the adults.  

Second, the technology, and the impact of this technology is less than 10 years old.  Everyone is an amateur in the internet.  Ten years ago, we all laughed at Bob Dole for mentioning his website during the debates.  No one knew that you could raise money with a website until Dean did it 3 years ago.  Does the netroots participation lead to votes?  I don't know, but only an idiot would write off the technology.