"I wouldn't take swimming lessons from a guy who never went into the water and tried it himself."
Well put. As the guy who had the, um, brilliant idea to start this place, I'll avoid speaking in the abstract and instead I'll actually give you some facts about my own situation:
My family is debt-free. We have no outstanding mortgage, loan, or credit card balances of any kind other than revolving credit on cards that we pay off in full each month. We like the convenience of credit, and use no-fee cards with points.
We have a net worth that places us, statistically, somewhere (being purposefully vague) in the top quintile (20%) with respect to other Canadian families—and that group includes families with breadwinners at more advanced ages (i.e. closer to the end of their wealth-accumulating years.)
Both of those facts at least suggest to me that we're on our way to meeting our goals.
On the other hand, I know we're not there yet. It isn't hard for me to calculate that if we didn't work at all, we would drain our financial assets well before we'd reach our own retirement ages—and even if the markets were to reliably provide decent (but not spectacular) returns.
So, we've got a long way to go before we are financially independent, i.e. depending on no source of income other than what our investments generate. I continue to hope for, but not count on!, many years of spectacular returns so the way can be shorter, but more realistically there will be (and have been) rainy days along the way. I've enjoyed the flexibility and luxury of taking some, ah, "calculated risks" with my career that I might not have otherwise taken if we lived paycheck to paycheck.
But I can say without a doubt that practicing—most of the time—the kind of advice I teach has had a significantly positive impact on our family finances, and I know when it comes time to send the kids to university that we won't be scrambling to pay the tuition*.
(* Assumes tuition inflation won't exceed a well-diversified, low-fee portfolio's returns. :)