Because I held my pants up with a belt and suspenders, I used to have a filter before the pump and another after it. Then I was told that the filter before the pump was a no-no because, if clogged, it would cut the flow a fuel to the pump which could result in a ruptured diaphragm. So, I removed that filter and, for good measure, stopped wearing suspenders. I suppose that, like with so many other things in life, there is often as good a reason for doing as for not doing whatever you do.
Bob S.