That is a very good question.
First yes all of my clothing listed is in my pack to start.
Clothing
Wind Shirt 90 Montane Aero
Down Jacket 232 MB U.L. Inner
Combi Hat 34 Turtle Fur
Gloves 30 Poly Pro
Cuben Stuff Sack 6 Med
Sub Total 392

What I have on is: REI Sierra convertible pants, Mountain Hardwear Canyon lands coverable shirt, Columbia mesh boonies hat, Pearl Izumi cycling socks, and New Balance 471 running shoes.
Now let’s give a hypothetical situation of stopping in the evening after day one. As things cool down the first thing I do is put back on the legs to my pants and drop the sleeves back down on my arms, next comes out the wind shirt, and turtle fur hat (which I love because it can be a hat, neck warmer, face mask, baklava or anything in between).Then if the temps drop more the wind shirt comes off and the down jacket goes on and the wind shirt over that. The gloves actually are not necessarily for warmth (though they do provide some) but for handling my hot pot and food container. I can take that system down to about 1-4 C (35-40 F) If things get colder than that I dive into my sleeping bag.
Morning time: Usually starts out with turtle fur, and wind shirt. As I heat up they come off and get stowed in the pack. The boony hat may or may not go on depending, then of course leggings come off, and sleeves get buttoned up.
Now here comes rain, on goes the wind shirt and boony hat, the wind shirt odes not provide protection from a down poor, but I don't mind getting wet, I am a hot hiker so I can stay warm as long as I am moving. My legs’ getting soaked does not bother me either. All of my clothing is very fast drying even if it is not sunny out. In the event of a deluge I put on the trash bag (though I have never done this, it is for the just in case, but I have not ever been driven to do so)
In camp and under my tarp off comes the wet clothing, and I would put on the down jacket or actually wear the wind shirt alone because it will dry just with my body heat in about 15 minutes, and about an hour for my shirt and pants. But let’s say I am just soaked and shivering. I would strip down, put on my jacket and climb in to my bag. Rig up my clothes line in my tarp and hang my "cloths out to dry" and just do everything from inside my bag. I have actually had to do this treatise before when I got flooded out (literally) of the trail I was on. It rained about 10 inches that night and day, and this was the only way I get anything dry.
I hope this provides some insight into my methodology or madness which ever it may be.
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