Everytime is viable. But not enough of it is fun. Its based off primary and utility weapons. You either are backlining with a support weapon like a Disrupter, Ravager or Pulse carbine… or just using anything else. I see no weapon variety for just running it down unless you have an assault rifle.
The fun weapons like sticky, SAW, railgun, spartan laser, all gone. You die so fast in BTB you cant go past two kills with energyswords or hammers unless you are just backlining even with an overshield.