I found the last part is very amusing....

..The author wrote "..If you don't want to replace the filter unnecessarily, you can remove it and check it to see if it passes air easily (More information on replacing fuel filtersis available). If the filter creates any significant resistance when you blow through it, it needs to be replaced..."

My questions are: 1)the filter is wet with gasline, and you want to test it with air. How accurate can that be?
2) if you have time to take the filter out from the gas line, why don't you just replace it with a new one? I wonder if the author ever changed a fuel filter before.