Hay Hud it appears our approach to the universal laws of hay curing are very close.

When I use my Khune mower it has the swath board removed, and gives me close to 90% of the ground covered with hay.

I can sympathize with those who are adverse to driving on down hay, but I noticed the hay on the ends did not suffer from being run over a time or two. As for a good heavy cutting not drying just laying out flat, well yes that is true. Hay that is not exposed to direct rays of the sun will dry at a rate dictated by soil moisture, wind velocity, humidity, temperature and any of the other factors that make up the 25% of drying done by other than direct sunlight.

In that case one or more times over with a tedder is appropriate. For those worried about shedding leaves with a tedder, it is redundant but accurate to say hay raked, or tedded with the humidity above 70% will have a very minimum of leaf loss.

I have friends and neighbors as well as a few academic types who also express misgivings about raking damp hay but have no problem baling bone dry hay. Here the key is to keep the PTO RPM's low and stay with damp hay. Run a tedder at 540 PTO and the hay will fly as will the leaves. That is why I emphasize use an operator on the tractor not a driver.

My early Spring time hay harvest are much as others tell about though only with roughly 12 hours of day light. At this time I lay down only one field at a time, so if the weather turns cloudy but with no rain the hay will be ready before it does rain, while 2 or 3 fields laying out at least one will become wet, and moldy. So yes hay left undisturbed the hay next to the ground will be slow to cure, and the top will bleach. I have seen hay layered in a windrow, be raked 3 or 4 times to turn the damp side up. At the same time my hay was tedded one time and raked one time, and baled one or two days earlier than the neighboring hay. To be fair their hay is oat hay while mine is alfalfa, that time of year.

We should be able to agree that though the rules for curing hay are fairly universal the application of these rules will vary according to individual climate, soils, management styles and equipment.  

My personal challenges are to bale during a 2 maybe 3 hour window of optimal hay moisture, and our annual summer drought.