May I contribute as an qualified engineer? I read here 5-6 times oil change a year. May I ask how many miles you make between oil changes? With so many oil changes it is rather useless to change your oil filter, because the oil doesn't get time to be contaminated with parts, big enough to be filtered by an oil filter. That's one. Number two is, re-usable filters are a fairytale when it comes to filtering capacities. Every filter is designed with a certain 'mash number'. Which means that particles bigger than that mash size are filtered out. During the oil filtering process these particles clogg the filtermaterial, till the by pass oil pressure lock is nearly full open and the filter is bypassed. When you read an 'excessive incrrease in oil pressure' in the use of a re-usable oil filter my hairs will rise in suspections. Because an increase in oil pressure means that the filter resistance is drastically decreased. Which indicates that there is a bigger 'mash size' in the filtering material. Or better: the filter gives a false feeling of being save, because the size of filtered particles is increased. That means that smaller particles (causing the wear inside an engine) which were originally filtered out, will pass the filter now. But because of the quicker oil change it will not cause damage to the internal parts of your engine. But keeping the original intervals in oil change or (in my case) extended intervals in oil change(because of the superior qualities of modern lubs)
an adequate and good oil filter with the original mash size of the HD can make the difference in early wear or extended life time of the engine.

 

So by your thinking when I change my oil and go for a test ride, by the time I get the oil good and hot and come to the first red light, the reason my oil pressure is sitting at 20 psi at idle is because my filter is already clogged up. As an engineer, you don't suppose it has anything to do with the increased flow through the filter do you?? I'm happy with a 22 micron filtration, which is equal to a particle size of 0.00086614173228 inch. or eight ten thousandths of an inch. According to the manufacturer of my filter, the area of the mesh is capable of a flow rate of 22 gpm.