Why? Apart from 401k's and other stuff that I don't understand being non-American I would say this is excellent advice for 90% of all people. Just pump excess money in a Vanguard targeted retirement fund (or something similar) and forget about it.
Well, his specific suggestion was an equity index, not a fund of funds target retirement fund. So, I should qualify my original reaction. Using a target retirement fund wouldn't be a terrible choice, certainly better than a straight stock index. My biggest objection would be the "forget it" part. Just ignoring your savings/investments is how you wind up nearing retirement in 2008 with all your assets in stocks and wondering why half your money disappeared at such an inopportune time. Any advice that doesn't include suggesting someone be actively engaged in understanding what they're investing in and why is incomplete at best.
I definitely agree with what you're saying.
I just wish more people take the time to understand basic financial literacy and long-term investing.