This is correct. I have spoken to AFE directly and they have told me that the cleaning ability is in direct relationship to amount of flow. In filters of identical size and surface area, the standard (5 layer oiled) flows the most and filters the least. The pro-dry (what I am using now, switched from standard) is in between but does not need oiling. The PG 7 filters the most but is also most restrictive in flow and requires oiling.

With the filter minder, when the truck was stock, the minder never moved clean or dirty. (I never let it get that dirty!). When I got smarty, it would start pulling down a fair amount. I changed to an Airaid filter and the minder would barely pull again. Then boost fooler and boost elbow with smarty beta 4.4 (still stock turbo and intake) and I'd pull the minder 3/4 down. I'm simply trying to point out the relationship that extra fueling and thus more air has on that filter minder too and it is not just simply a dirty filter. Hope that helps!