This is exactly right; although not all "proper" theaters have two projectors. Where I work we have one and a "long play" tower which allows us to play the whole film with one projector.

Many still do run changeover systems, though.

(In case you're interested, I work in an indie cinema in the UK, and we're really scared about the costs of changing to digital, which we will need to do in the next 12 months)