Narrative of Light Armor Proficiency

[Blue]

I understand the gamist reasons why it exists, but can someone give me a good in-game narrative why wearing "supple and thin materials" (from the PHB description of light armor) will give me disadvantage on all ability checks and all those other penalties?

"I'm sorry, your ability to know about nature has been greatly reduced because you are wearing winter clothing or a leather jacket and chaps."

Again, just looking for a general in-game narrative, I understand the game design reasons behind it.

 

[Keith Lamond]

In real life, I've worn protective leather (motorcycle racing gear) and can tell you that it makes movement a little harder and it's heavy compared to normal clothes or robes. Light armor is supple and thin when compared to medium armor, but it is less flexible than regular clothes. Less flexibility would make it harder to do things requiring dexterity like getting out of the way and casting some spells.

With practice and perhaps some training, you can learn to compensate for the inflexibility of light armor. Hence the ability to take a feat to allow it.

For some classes, wearing leather armor may go against a tribal or religious belief. Are you really tough if you need armor to protect yourself? Do the chemicals to tan leather harm the land go against a belief that nature must be protected above all else. Your conscience or pride may impose a penalty for wearing light armor.

Game mechanics don't always make narrative sense, but it is possible to find ways to explain penalties for wearing light armor.

 

[Hriston]

Wearing armor you're not proficient with wouldn't give you disadvantage on an Intelligence (Nature) check. It only gives disadvantage on checks, saves, and attacks involving Strength or Dexterity, and you can't cast spells. Performing physically and fighting in armor requires training. You'd have to get into the specific materials a set of armor is made from to form a narrative for why that is. Leather armor, for example, includes a breastplate and shoulder protectors made of stiff, boiled leather, not just a leather jacket. As for spells, wearing armor you're not proficient with is too distracting to mentally focus on the spell, and it gets in the way of performing somatic components.

 

[Laurefindel]

I know that when I'm in pain, when I'm exhausted or when I'm severely inconfortable, i have a hard time thinking straight. Would wearing a light armour I'm not proficient with cause me enough pain, exhaustion and incomfort to warrant disadvantage on "knowledge checks"? Probably not right away. After a few days perhaps?

(One of) the beauty of 5e is the rationalisation of bonuses and penalties as advantage/disadvantage. The drawback is that it doesn't differentiate light handicaps from serious ones.

So could it affect your ability to recall things? I see it more as doing "beginners mistakes" while you should have know better if you had a more rested mind. As you said, its more a game construct than anything, but I don't see it completely devoided of sense.

 

[Shiroiken]

The PHB description is actually wrong from a historical bent. Padded armor is neither thin, nor supple, since it's similar to wearing armor made of phone books (Mythbusters had an interesting episode about that, btw). Leather armor is actually boiled and hardened, so it may be thin, but is not especially supple. Studded leather is a misnomer, since it was based of drawings of brigadine armor and never actually existed, but brigadine would have been thin, but also not exceptionally supple. Given the historical context of armor, the proficiency penalty actually makes a level of sense.