XP Bar Bug

Описание: This is a short video I made to demonstrate the misleading XP bar bug. Whenever you earn a bunch of XP in a zone, and then go to another zone (or reset the current one), the bar resets backwards. This is easy to see on low-level characters. It can be seen in at least this activity and node farming... feel free to test other activities.

27 XP * 18 orb = 486XP.
The total bar on my level four mesmer is 2647 XP.
That means each orb is roughly 1% of an XP bar... so just short of two segments of the bar for this dive.
Before I go through the portal at the end of the dive, you see the bar tells me I got roughly 3.75 sections. (37.5% = 992.6) This is double what we are actually getting by the values flashing on the screen!
Once the "instance resets" the bar returns to what I expected based on the numbers on the screen.

So which one is correct? The numbers on the screen and the reset XP bar after instance change or the XP bar as we are earning the XP?