oil filters

I have always changed my filter halfway between my oil changes so I dont worry much. If my oil change interval say, with my subaru is 6000 miles with synthetic oil, I change the filter and top off with fresh oil at 3-4000 miles. A wix filter is 4 bucks so its cheap insurance to replace a partially clogged filter. I have always done this with all my vehicles. Even the claims of the boutique oil makers claiming 5 figure intervals, imagine a filter at 12000 miles. Can you say "bypass valve"?