Points in an inch vs. gridlines vs. font size pts.

[doctorduncan]

I am working on a sample title page for our students to use in formatting their papers. I am trying to create a "ruler" in a vertical text box that shows


6 pts
12 pts
18 pts
24 pts
etc.
I am having a very hard time, with everything being Times New Roman 12 pt., lining up a single line of text with any of these numbers.
If the entire page is in a 12 pt. font, then the page, and presumably the gridlines, should be divided into lines of 6 points high, should it not?

As I understand it, there should be 72 points in an inch, at least if a font is Times New Roman 12 pt. However, I'm running into some difficulties. I turned on gridlines but I cannot tell what size the boxes are. They don't correspond to any wording on the page, which is all 12 pt. Times New Roman. That is, they are clearly not = 6 pts. verticially. 1. How big is a gridline box?
2. Arial and Verdana are larger than Times New Roman when each of these is 12 pts. That is, apparently the size of a "point" depends upon he font size. So how can anyone say that there are 72 points in an inch? Further, when I look at a page done this way, 72 points looks like it is longer than an inch in Times New Roman 12 Pts.

So the gridline boxes don't mach 6 pts each, which is the height of a single line? Or is a single line 12 points? It depends on the font size, right?

I wish MS Word did not have this concept of points. It makes life difficult and that's about all, so far as I can tell. Thanks for any help.