Logic does not delay compensate while playing, if you add a heavy plugin on a channel it will play along whiteout any hiccups.
But the track you added the plugin on, will be out of time, until you hit stop. When you hit play again all will be in time again.
I just mentioned it because I have seen Logic users complain that they want delay compensation like in Cubase
Just add, someone @ Steinberg already have said they are working on eliminating (if possible) and/or reducing this annoyance in the future. It sounded like a major rewrite would have to be done, but they are working on it.