I am not sure if this is a bug or not:
Ok so when I duel a friend this is what happens with barriers (both chars are in the same spot):
In total my friend has 6600
I have 6297
Obvioustly: his barrier stays
His single char: 1769
My single: 1706:
Obvioustly: his barrier stays
Now for the interesting part (we removed a few runes from his char):
His total: 6305
My total: 6297
My barrier stays - which is weird
Then we tried adding on runes one by one:
His total: 6380
My Total: 6297
His barrier stays, which is normal
As for single char initiative
His: 1604
Mine: 1706
His barrier stays - does not make sence
Only when we dropped his single char initiative to 1474 versus mine 1706 - thats when my barrier stayed. But at this point, its the scenario, where his total initiative was still higher at 6305 vs mine 6297
So this does not make sence and seems bugged does not matter which way you look at it: single char initiative or total average.
I checked the forums, I know this gets ever weirder in arena, but this was the on map duel that was tested