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The short answer to the Quiz question is "No." Here's why...
This was from a recent service call I did for a washer with very low cold water flow. I had been out on this washer just a year ago for the same problem. I found the cold water side of the inlet valve packed in with sediment (the house is on a well). It was so far gone that I had to replace the valve and I advised the customer to have a plumber install a whole-house sediment filter, which they did.
When I went out on the call, I found sediment in the cold water side of the valve again. I showed this to the customer and she became distraught.
"But we installed the sediment filter like you told us last time! I thought it was supposed to stop this from happening. Why didn't it?" she asked.
I asked to see the sediment filter and this is what I found. Turns out they had forgotten to close the bypass valve after the last time they changed the filter. When I pointed this out, the light bulb went off in her head.
"Oh! That's why this filter lasted so long! The first filter we had to change after two months because it got so clogged with sediment. This one has been in there ever since and it still looks new!"