Just read Joe Henderson´s "Long Slow Distance - The human way to train". Since I was forced to train very relaxed because of an Achilles tendonitis last fall, I´m on my metamorphosis to a LSD-runner. I think Henderson´s method isn´t the best nor the worst. I´m training consistently and enjoying every run because I´m relaxed. Love it!
(that doesn´t mean I won´t run faster when needed - it´s just about the very relaxed approach)