You need to identify the win condition of your team setup. Dedicating 50% of your ninjas towards being reactive towards an enemy basically means you're either very confident in your standard attacks (or a carry ninja) demolishing the enemy, or you're playing a drawn out game designed to fatigue/DoT the enemy to death. The hard thing is that a lot of ninjas are immune, or dodge in the current meta, which basically means your mysteries are of 0 use - and you have a -2 skill handicap (not to mention lag in the server messing things up). There are just too many team setups that would beat a 2 interrupt team.