This explanation is kind of confusing, here is an easier way to look at it:

If something is X, only because of its relation to something else, then it's relative.

If something is X, regardless of anything else then it's absolute.

I've heard that it is useful to study them but also to keep in mind they are not the end all be all for identifying a premise/conclusion.

When looking at stimuli, we have to remember to keep the outside world out of our heads. It is frustrating, but super helpful! A lot of the time, stimuli make no sense in the outside world.