What is (setq comment-style 'aligned) supposed to do?

Question

First let me show a few things that work correctly. I am doing everything shown below using emacs -q foo.txt in a text buffer.

I make these settings first:

(setq comment-start "<<")
(setq comment-end ">>")
(setq comment-style 'box)
(setq comment-column 25)

I have this text buffer:

The quick brown fox
jumps over
the lazy dog

If I select the three lines with C-SPC C-n C-n C-n and press M-;. The buffer becomes like this:

<<<<<<<<<<<<<<<<<<<<<<<>>
<< The quick brown fox >>
<< jumps over          >>
<< the lazy dog        >>
<<<<<<<<<<<<<<<<<<<<<<<>>

All good. This is what I expected. Now I undo the change and revert the text to original state.

But now I change the comment style to:

(setq comment-style 'aligned)

Then I select the three lines of text again and press M-;. I get this:

<< The quick brown fox >>
<< jumps over >>
<< the lazy dog >>

The comment ends are not aligned. I was expecting this:

<< The quick brown fox >>
<< jumps over          >>
<< the lazy dog        >>

Is comment-style 'aligned supposed to align the comment ends or not? If not what is 'aligned supposed to do?

---

The value of comment-styles on my Emacs:

((plain nil nil nil nil "Start in column 0 (do not indent), as in Emacs-20")
 (indent-or-triple nil nil nil multi-char "Start in column 0, but only for single-char starters")
 (indent nil nil nil t "Full comment per line, ends not aligned")
 (aligned nil t nil t "Full comment per line, ends aligned")
 (box nil t t t "Full comment per line, ends aligned, + top and bottom")
 (extra-line t nil t t "One comment for all lines, end on a line by itself")
 (multi-line t nil nil t "One comment for all lines, end on last commented line")
 (box-multi t t t t "One comment for all lines, + top and bottom"))