Is level sync'ed XP "true level relevant?"

[Raldo]

What it's looking like is that, while the numbers you'll see are always relative to what level you currently exist as, the "progress along your bar" is kept as you level up and down.

It does not work like this. The exp you see is the exp you get. Try doing a lv15 dungeon, you'll barely move your exp bar at all, whereas a lv15 would get nearly an entire level.