It is not a bug.

Barrier: Total attack speed
Who goes first per postion: depends on the ninjas gear.
Some ppl prefer to stack it on 1. and/or 2. postion, other ppl prefer to have more total attack speed for barrier.

Tipp: Use your 1. round to ensure who goes first in 2. round. The ninja who does his standard earlier will go earlier with his mystery as well.