I dont know that BLM is the best example for your theory. The correct rotation changes every 10 levels or so, but the game stops teaching useful techniques by like level 10. The class quests focus on sleep, begging for mercy, crying, and running away. They might teach transpose, but this stops being standard before level 50(falling out of the "rotation" into the "post fight" or "edge-case optimization" categories). They never teach how to effectively use flare(or its single target version later). In AoE situations double(up to quad!) flare is the intention, but they teach none of that - you need to piece it together yourself from trait and spell descriptions or find a rotation guide on the internet.

All of which is to say, bad habits are just as easy to develop getting one skill at a time as they are to develop with a class that starts at level 70 with 90% of its kit in hand.