As of 7.1.5, in addition to the 10% proc nerf, Magistrike Restraints can no longer proc more than once per cast. Even with Havoc.
Prior to the patch I sometimes got 4-6 total Chaos Bolts out of a single Havoc Chaos Bolt cast, however now you can't get more than 3.
The one additional bracer bolt can peoc off either havoc or the original bolt, but not from both.
This is a huge nerf and went undocumented, it makes the legendary pretty bad, which is fine, but if I'd known about it I would've put more effort into off specs.
I've made tweets to no avail to the devs. I don't know if this is intentional or a bug, but if anyone can find out that'd help a lot.