Yes, you are correct. It does work. I created the separate comment, set the font size. Copied the text out of that comment label and pasted it into the middle of the button's text.
I didn't think it would work because I tried something similar where I went in to edit the control and dropped a comment label on top of the button. So the button would have " this is text" with "BIG" has a separate comment label dropped in the space. But the area covered by BIG was not clickable on that button.
It does seem odd that if you were able to select a portion of the button text in older versions and could change the size of just that portion, that it was later taken away. Especially since you proved that you can have different font sizes within the text if you do the work around you posted.
