Wiley your on to it!OK, I'll add to Andy's original confusion with a question of my own (hijack)
Looking at the C and then at the D, unless we play the entire 6 strings (or 5 in the case of the C) and play only the bottom 3 (or 4) we have the exact "shape" we would have using the C, do we not?
Example: D pattern, Barre at 5th fret
--------5-------
--------6-------
--------5-------
--------5-------
X---------------
X---------------
Example: C pattern, Barre at 5th fret
--------5-----
--------6-----
--------5-----
--------7-----
--------8-----
X-------------
Perhaps I have answered my own question, EXCEPT, that D pattern moved and became an "F" chord, as did the C pattern? So, by using the C pattern, are we not actually doing no more than 'embelishing' the same chord with a fuller/richer bottom end? Not that it would be a bad or undesirable thing in certain cases!
...but your 2 example appears to me using "same" major C scale pattern which now has become F chord and F scale
Ex 1 would be F/G chord F with G in base when played
Ex 2 would be full F chord as a C shape
Your Ex1 should be
--------5-------
--------6-------
--------5-------
--------3-------
X---------------
X---------------
for D pattern usage for F chord and scale
hope were on the same page and I haven't muddy the waters