Yes and No, mostly no though. They tell people things like that mostly because it rakes in cash monies for them. For example, "Course X" could have "Student Y" who was blisteringly amazing, and worked his ass off in and out of classes, and then went on to work for "Company Z"... Course X can now legitimately claim that…
The 2.5D snaps are useful to relatively align a vert selection with some other vert outside the selection. Like along a xy, yz, zx plane but not all three axis at once. 1. Turn on 2.5D snap - make sure vertex is checked on in the snapping options, it helps to turn off most of the other snaps as well. I usually just left…