D6: TabViewXP>>paintLabel:on:in:

What's the rationale behind the y-shift of labelRect in the line

  labelRect := labelRect insetOriginBy:
    textOffset @ (inverted ifTrue: [-1] ifFalse: [1]).

which is the second-but-last in the method mentionned above?

I'm asking because I have noticed that the lowest pixel row was missing
from the tab labels when using XP's eye candy, but not when using the
old-fashioned window style. If I change the statement above to:

  labelRect := labelRect insetOriginBy:
    textOffset @ (inverted ifTrue: [-1] ifFalse: [0]).

the last row of pixels appears on the screen. For now I'm boldly using

  labelRect := labelRect insetOriginBy:
    textOffset @ -1.

and wait for the world crashing around me...

s.