I think there's an underlying principle missing from the list, but clearly implied by all three principles and by that little "Different strokes" comment. Unlike the "new school" gamers, OSR participants do not believe there is one way to do things, not even in one way to do specific things; it's always a search for the most pleasing way to do it for ourselves, based on what we currently want. It changes from person to person, from time to time.
The point of "D&D is Always Right" is not that older versions of D&D are the most perfectest game evar!!1!one!
There can be no such beast, because what's fun for me may not (probably even is not) fun for you. Different strokes and all that.
When you read posts by 4e champions defending their game, there's a lot of discussion of game balance, fixing "broken" rules, using "modern" design principles. All of these statements imply a "right" way to do things.
When you read posts by old school champions defending older editions, there's a lot of discussion about why game balance doesn't really matter to them, why they don't think the rules are broken or even whether there is such a thing as a broken rule, and why they don't really believe in the evolution of game design. All they care about is sharing their personal approach to fun, just in case it inspires you to find your own fun.
Old School principles can support new school games, but not the other way around. That's a distinction worth thinking about.