T&T: Fuel Return lines/ Fuel tank design

[Mark Andrew]

Quick question...

The fellow who sells the polishing system I'm considering suggests that the
return line enter the tank from high up, then be tubed down to about an inch
above the bottom of the tank...this is to disturb any sediment at the bottom
of the tank as the return fuel rushes back into the tank.  

Is there any reason I couldn't/shouldn't plumb a return nipple into the side
of the fuel tank (steel) 1 inch above the bottom to serve the same
purpose?...in essence, what is the point of entering from the top, and
plumbing to the bottom, rather than just enter the tank low down to begin
with?  Assume that the return entry will have a shut-off valve on it.

The return from the engine/gen set/furnace is very low pressure (I think),
so it should probably be up high, and just drop into the tank.

Any thoughts on return line placement?

Thanks,
Mark