The only thing Ill comment on is the tree cover, as that was from my post.

What you described is a radiation barrier.  You thermally radiate to everything you can see.  For instance, thermal radiation happens between me and the wall next to me, but not the wall beyond that.  The frequencies that thermal radiation occurs on prevent it from being anything other than line of sight, unless you do some crazy physics things, but thats not what we are talking about here.

Putting it in terms of giving and receiving doesn't make much sense, there is only heat transfer. Oranges will radiate to the blanket, or they will radiate to the sky.  The rate of heat transfer due to thermal radiation, varies dependently on the temperature differential, the emissivity of the orange, and the absorption of the surrounding objects.

Clear, open space, is a black body with an extremely low temperature, and high absorption. So when you don't want heat transfer to take place between your oranges and that body, you put something between it to block the radiation.

Humidity affects two factors that determine how you feel: conduction and evaporative heat loss. At a given temperature, one loses more heat by evaporative heat loss to dry air than moist because dry air has a lower partial pressure of water vapor and thus can absorb more water vapor. When liquid water evaporates, it releases heat, which cools the surface containing the water. In winter, however, most of us non T-shirt in 30 degree wearers have little in the way of exposed skin and so lose little heat to evaporation. However, humidity also affects conduction if there is sufficient moisture to condense on warm surfaces. Moisture on the surface of a coat or skin can increase the conduction across the coat surface or skin, leading to greater heat loss and feeling colder.

Ok you got me on evaporative heat loss, although I am not sure that in cold weather this has much effect, both because of the clothes and because you don't sweat in cold dry weather, unless you are doing some serious exercise.  As you said, it would be a factor in humid cold weather, which only better supports my point.

Those who argued that it is radiative heat LOSS that causes you to feel colder on a clear night are also off by a little. Radiative heat LOSS is strictly a function of the your surface temperature, which would presumably be the same regardless of the night sky.  In fact,a clear night sky is colder (the temperature of the upper atmosphere) because it radiates less heat to the ground. NET heat loss by the body is therefore greater because the body receives less radiation from the sky.

Also true, which is why I was talking about total radiative heat transfer, which is a measure of the Qrad total between two bodies.  As I said, on a clear night, the Qrad between the sky/clouds and the earth is much higher due to temperature^4 differential.  So we stated pretty much the same thing.

The reason you can wear a T-shirt on a clear, non-windy 35 oF day is because solar radiation is high and unreflected by clouds, and this heat input is sufficient to make a person feel like it is 40 oF warmer.

While I agree that a non-windy day is essential to keep the energy transfer low and the solar radiation does have an effect as I stated in my original statement, you seem to be glossing over the fact that there is still a palpable difference at given temperature (especially cold temperatures), between humid sea level air and dry thinner air, and this is mostly due to the difference in thermal conductivity, as was shown in both of my linked to examples.

I guess it depends on your type.  Both schools have an abundance of amazing looking girls.  
I always said that the girls in Austin look better when you meet them that night because they get done up more, but the next morning the girls in Boulder still look similar to the girl you met the night before, which can't always be said for Austin girls.