I don't think it's 1 gem in 3 days, considering it first told me "Log in 6 more days to get 1 free gem!" I think it's something new. Like a guaranteed gem/week.
I just had 3 Arena orbs where I went 0-3. During those 3 battles I had 11 chances at a BB and wen 0-11. Meanwhile my opponent had 5 chances and used all 5.
I think I've convinced myself that the way they "balance" the Arena in spite of the overwhelming advantage of going first is by giving the opponent a massive increased chance to use a BB.
Which in the Lodin/Lira/Falron/Ophelia/<insert light/dark unit here> days we live in is total crap. And I thought the Serin-brigade was bad.
*EDIT* Have you guys seen this?
http://bravefrontierpros.tumblr.com/rawskillsdb?
Someone on Reddit extracted the raw data, and the bravefrontierpros people put it in an easy searchable database. Interesting stuff.