A number of years ago we were told to state either and or Satanas/Aum. Short Satanas in one breath(not long SATANAS with breath per letter) and or Aum.

These are for affirmations so Satanas/Aum Affirmation Satanas/Aum.

Can someone remind me why we should or should not perform Satanas/Aum before affirmation and after affirmations.

I know Aum, so mote it be. From the Aum webpage. But...

But what's the science behind stating S/A Affirmation S/A?

I recall it has to do with adding power but I think there is more to it than what was said. And if it is about adding power, is it wrong to mix these Sanskrit words with the energy raised beforehand. In other words is it okay to use these energies when encountering the affirmation phase.

(I've lately actually a while now have been pumping Satanas/Aum F-RTR Affirmation Satanas/Aum. Is that okay?)

SATANAS gives the affirmation more power and AUM realizes/brings about what you're affirming. AUM also works as a 'checkpoint', it 'assembles' and keeps the energy raised together.