Not sure how this applies to the OP thread, but may be so.
I'm sure how it applies to my thread. Answer: It doesn't! LOL.
If it were water in my tank, then I would be having issues every time the vehicle sat for a bit and was restarted. Furthermore, if there was a large amount of water it wouldn't start, or run.
This vehicle is used often and regularly gets down to less than a 1/4 tank before being refilled with a fresh batch (in other words, fresh gas is continuously being added and cycled).
Again, it's not a one time problem, it happens EVERY time I add at least a few gallons of fuel, and ONLY then. Meaning, after I refuel (and get it started) the problem is 100% gone until the next time I get gas.
As I see it, the only thing that it can be is the mixture (with the purge valve connected and operable) is too rich for the engine just after fueling. What is causing this to be the case is what I can't figure out.