A few things:
1) If so, so what? Without a practical application- and I can see none- this isn't a rule, it's an observation.
2) The top and bottom parts of your second and third examples are not the same length- you can't just freely exchange an 8th note with a 16th note+16th rest. They may sound the same when you play them on a wood block, but they are different values. In every example the originals and their inverse have the same duration.
3) I don't understand the relevance of the beams- wouldn't the rule apply to any collection of notes of different values?
4) What about a rhythm of 16th-8th-16th?