Armor level has little to no bearing on the defense quality of an item, only what kind of armor the dwarfs consider it to be. 1 is leather, 2 is chain, and 3 is plate.
Given the new military screen the tags may be vestigial, though I would guess they play a role in determining the equipment of invaders and neutral military units.
The actual effectiveness of armor is now determined almost entirely by the materials it is made out of, though I imagine coverage, layer size and some of the misc. tags play a role as well.
I'm not sure about socks in .31, I am curious if whoever wrote that in the article actually tested it, or just assumed that since that was the way it was in 40d, that's how it is in .31. I am suspecting the latter.
Sorry, my fault, it is an incomplete edit(it is fixed now). I meant to pull that out when I was rewriting the armor table but forgot.
ooh that is logical the 1 and 2 and the 3 refers to armor type!! xD
so cloth is 0 very simple
So a cape with coverage 50% only gives half it's strength to defend against attacks against back / torso area.
So in the end its material type and size? ok i'll see what i can do with that.
In 40d, coverage was used in determining the exposure to temperature effects and such. I don't think anyone has checked on if coverage has an added effect now or not.
Each item of clothing on a certain body part adds its 'layer size' to the total. Once this total goes above the 'layer permit', nothing more can be worn there.
So looking at what you've quoted from the raws, a dwarf could wear two pairs of socks at the same time (10 < 15, so we can still add more... but 10+10 > 15, so we have to stop at two).
This probably limits them to socks + shoes OR socks + low boots, since shoes and boots should be smaller than socks.
I think coverage is how much of that body part is covered by the item, so socks cover 100% of a dwarf's foot.
If there's no mention of armor then the info on the wiki may be wrong. I've seen some combat reports where clothing deflected attacks, but I can't remember socks being one of them.
[LAYER:COVER] items are the only items playing by the old rules I am afraid. I am still working on how to present the new rules but I know the logic works something like this.
If the item to be add is a [LAYER:COVER] item, add the total item size on the body part, if this sum is
less than or equal to the item's permit value then continue.
If a [LAYER:ARMOR] item is present or to be added and if the sum of the non [LAYER:COVER] items would be
less than the sum of the [LAYER:ARMOR] size+permit values then continue.
If one or more items of the same non-[LAYER:COVER] layer as the one being added are present and if the sum of their size values is
less than the smallest permit value then continue.
If the sum of the size values for all items on the body part are
less than or equal to the permit value of the item about to be added then continue.
The item is allowed if all rules either evaluate to true or are not applicable.
EX: A helm(30 size,20 permit) means you can put on a mask(20,10) or two caps(10,20), but only two head veils(10,100). Any of these configurations can fit 6 additional hoods if desired.
EX: Wearing a cap(10,20) means you can only put one face veil(10,100), because they are both [LAYER:UNDER]. But you can have up to a combined total of 9 head veils and hoods.
NOTE: This is also in compliance with the [SHAPED] tag that prevents more than one of an item at a time with the shaped tag on a given body part.