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.

I've heard this before, and I don't really buy it. The pump itself has a strainer which could also become blocked. I'd rather have a blocked filter than a blocked pump. And the inline fuel filters are usually transparent. You can see how much dirt is in there. And even if it looks clean, you should replace the in line filter at least once a year. They are cheap, therefore cost is no reason not to do it.