I wouldn't say endurance is more important than strength. I think balance is most important. By this I mean the muscles need to be balanced, abs and lower back need to be balanced, quads and hamstrings, etc. I know Scooby said exactly what you said on his site. http://scoobysworkshop.com/preventing-lower-back-pain/
I would expect that as long as you pay attention to maintaining muscular balance, you can prevent back pain. If you already have it, you may need to take remedial action.
By the way, strength and endurance are related. If you are strong, your endurance will improve since doing light work is relatively even lighter. Endurance does not lead to strength. Therefore, working endurance is likely only of value in a rehab setting.