I was doing some pre-winter maintenance on my daily driver it's a 2000 Ford F-150 truck (yes I own Chevy as well as Ford). That being said I changed the oil and then was going to clean the air filter. The air filter has about 20,000 miles on it since being installed last year

I went up to the auto parts store and bought the cleaning kit for $9 and sum change. This was the first time I had cleaned one of these types of filters so I read the directions. The directions stated in a nut shell:

1) Brush off any loose debris with a brush.
2) Spray on cleaner and let sit 10 min.
3) Wash Filter from inside out with water.
4) Dry by shaking off excess water and then air dry naturally.
5) Apply supplied lubricating oil, wait 20 mins. and reapply to any remaining white areas.

That's all fine and dandy but the things that got my attention were:

1) Clean every 50,000 to 100,000 miles to let the dirt build up work for you which will actually help increase performance? Huh?

Do not use compressed air to dry the filter after washing with water? Huh?

Well those two things didn’t make sense to me so maybe you guy's can help shed sum light on this?

How does a dirty filter increase performance? I can see that it might help trap more dust and dirt but that also means that it is getting less air because it's more restrictive?

What is wrong with using compressed air to blow the excess water out of the filter instead of waiting a couple of hours for the darn thing to dry?