Public Service Announcement: Using Thavnairian Onions Correctly

Thavnairian increase the level cap by 1 until lv20. The Chocobo have to be at the current level cap first before the cap can get increased. I thought that is common knowledge.
But i wounder why the Chocobo don't get automatic a level up at 1714000/1714000 but need still 1 exp? Was it feed in the stable? That it don't get a level up in the stable was also written in a patch note.

I didn't find the right solution from the Internet.

References:
http://forum.square-enix.com/ffxiv/threa...nions-Correctly

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