What would this be?

[quogueelectric]

That may be a stretch but it is certainly possible and that is a good point.

The pool bonding may be a better ground than say 2 groundrods and may be drawing most of any bad neutral current down the small ground wire to the pool ground grid/bonding.

 

[Pierre C Belarge]

The pool bonding may be a better ground than say 2 groundrods and may be drawing most of any bad neutral current down the small ground wire to the pool ground grid/bonding.

That is an interesting thought.
Only the earth resistance and the distance from the source (utility pad mount transformer in this case), would possibly make that a moot case.