Yep. Solid PT runs on a demand schedule too: during hours heavily traveled a train might run every four minutes; during the dead of night it may not run at all or run infrequency, like every forty-five minutes.

And to the GP's point, they most definitely take you from point A to point B. Those two points may not be where you are and where you want to go, though with a solid network it'll usually be within ambulatory distance.

;)