[shatner]

What the heck, just to really drive this last point home, let's look at a gratuitous communion: 8x A1S1 masters and 8x A1S1 slaves. Assume two of the masters each have a Crystal Matrix (auto-casts communion master on them at the start of battle).

Round 1: 6 of the masters cast Communion Master, 8 slaves cast Communion Slave, the 2nd-to-last caster (with a crystal matrix) casts Power of the Spheres and the last caster (also with a crystal matrix) casts Storm Power. If we only pay attention to their air paths, 6 masters have A4, two masters have A5 and each slave is an A3 but counted as an A6 for communion-fatigue purposes.

Round 2: Each master casts Thunder Strike. 6 are A4s, giving (50/2 )/8=3 fatigue per slave per casting. Two are A5s, giving (50/3)/8=2 fatigue per slave per casting. Each slave is considered an A6 giving them (50/4)/8=1.5 fatigue per slave per casting. That's 3*6 + 2*2 + 1.5*8 = 18 + 4 + 12 = 34 fatigue per slave per turn from 6 A4 and 2 A5 Thunder Strikes per turn. That communion can last for 6 rounds before the slaves start taking damage.

The first example got us 36x A4 Thunder Strikes over the course of 9 rounds before we started damaging slaves. This last example got us 48 Thunder Strikes over the course of 6 rounds, 12 of which were A5 strikes. Not only did it get us more damage, it got us faster damage. With path buffs, we microwaved the battlefield in record time. Without path buffs, that 1-1 master-to-slave ratio would microwaved our slaves even sooner.