This is the first time I have ever heard anyone refer to Dragonlance as "old school."
EDIT to add: in fact i would go so far as to say, in my experience, Dragonlance IS the break from Old School.
This is definitely a point of confusion for a lot of folks.
I'm among the folks who often point to Dragonlance as a transition/inflection point. From TSR focusing less on challenge/exploration-focused modules, to more on heroic adventure story-style modules, and novels alongside them. The so-called Hickman Revolution.
A lot of the hardcore AD&D partisans will exclude DL and 2nd ed AD&D from the old school, and to some extent that makes sense. But on the other hand, as
The Elusive Shift and early fanzines document, some folks were doing very story and character-focused D&D in the 70s, nearly from the get-go.
While "story-focused" isn't the first phrase that I'd normally pair with "old school", I don't think it's incoherent either. Some old schoolers were story focused. I think this mode of play is often referred to as "Trad", as opposed to "Classic", which is ostensibly the Gygaxian challenge-focused style, for example in RetiredAdventurer's
Six Cultures of Play essay from last year. Although I think he's a little bit off in saying that Trad play was necessarily a reaction to Classic, or that it didn't develop until the late 70s. The zine conversations referenced in
TES indicate that it started really early.
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