I hope you didn't take my answer as a "read the manual" type answer, I didn't intend it that way at all. There are several things I have read in the H and Cub manuals that don't fully sink in till I'm actually working on that particular part and read it again. Just like your question, I've read about the oil bath air cleaners a half dozen times and when I looked at it this time the light bulb went on! That's why I quoted the manual.
There's a couple more things in the "daily or every ten hours" catagory I'm going to pay a little more attention to. Rear axle bearings for one and as soon as I figure out/remember where the "Upper Bolster Pivot Shaft"
zerk is located (somewhere up around the nose cone), it's going to get "two or three strokes of lubricant".