Laying out patterns on patterned fabric

My Ultimate Sewing Bible claims that when I lay out my pattern on patterned fabric I should lay it out so that the pattern matches up at all of the seams. Logically, this should be impossible because the sections of the garment are not flat and square, and therefore if the pattern matches up at one part of the seem it won't at another. I tested this theory by looking at some of my clothes which are made of patterned fabric and this leads me to conclude that actually all you usually do is ensure that the pattern is the same way up on all parts of the garment and aim to get the pattern repeat at roughly the same level on all parts of the garment.

Is that correct?