Best Way to Recirculate for Immersion Chiller

I can't brew for a while, so I'm thinking over what I could do to improve my next batch. I'm planning on trying out Jamil's Whirlpool/Immersion Chiller.

Is it more efficient to recirculate through the IC with A) my coolant water entering to the top of the coil and traveling down or B) coolant water entering at the bottom of the coil and traveling up?

I would guess A since the hot water would rise, but my guesses tend to be wrong, so...

If you are recirculating, it will not make a difference on the direction of water flow.

Does it make a difference if you're NOT recirculating?

I'm not sure but I would imagine with the relatively small volumes we are dealing with it will not make any difference.