Oh, I agree, totally agree but the pain of the bookkeeping to enforce that.
The problem is the D&D uses entirely the wrong scale for encumberance. Tracking things down to a tenth of a pound (or even to a single coin in some editions) is just too much detail, especially since a character's load will change frequently (every time they use an arrow in combat; every time they find treasure).
Besides, very often the character's ability to carry all that stuff would be nothing to do with their muscles' ability to shift that load, but rather down to how well it is packed. (Think about it: how many dice can you carry in your hands? How many can you carry if you put those same dice into a really big bag?)
Note: this system works particularly well with item cards, since there's then a really obvious sign of what the character is carrying.
A
very simple encumberance system (and probably not a much less realistic system) could just allow characters to carry "ten things" (adjust number to suit), such as:
Leather Armour
Shortsword
Shortbow
Quiver of arrows (up to 20; any combination)
Potion (Cure Light Wounds)
Thieves' Tools
Rope and Grapple
Bundle of Poor Loot
Pouch of Monies
and so on.
(Of course, you'll have to make a call about what counts as one of the ten things. This probably shouldn't include worn clothing items, or the various containers a character might use. But how many coins count as a thing? Do two daggers count as two things, or just one between them? And so on.)
A
more complex system would split items into Major items, Minor items, and Conditional items. Major items would be the big, bulky items such as a suit of armour, a weapon, rope... Minor items would be the small, light items: a coin, a potion. Conditional items would mostly be clothing items - when worn, these are considered Minor, but if the character is just carrying them, then they'd be considered Major.
Then, in addition to the limit above, characters would be further limited by their Strength: they can carry a number of Major items equal to their Strength before becoming encumbered, then a further 3 items before being heavily encumbered, and then a final 3 before reaching their maximum load.
So, our theoretical thief above would be carrying a load of 6 (armour, sword, box, quiver, rope, bundle of loot).
A
more complex still system would replace the simple "ten items" limit with a number of 'slots' of different types. A character can carry an item if he has an appropriate slot available. Adding a pack would add a number of slots that can be used for anything.
So, our example thief:
Body: Leather armour (major)
Weapon 1: Shortsword (major)
Weapon 2: Shortbow (major)
Weapon 3: Quiver (conditional - consider minor; adds 3 "quiver" slots for arrows)
Weapon 4: Unassigned
Back: Backpack (conditional - consider minor; adds 6 "pack" slots)
Quiver 1: Arrows (up to 20; any one type; major)
Quiver 2&3: Unassigned
Pack 1: Rope & Grapple (major)
Pack 2: Potion of Cure Light Wounds (minor)
Pack 3-6: Unassigned
Left Hand: Sack (minor; adds 3 "sack" slots for treasures)
Sack 1: Bundle of Poor Loot* (major)
Sack 2-3: Unassigned
Belt Pouch: Pouch of monies (minor)
Concealed: Thieves' Tools
About Treasure
In the example above, I've listed "a bundle of poor loot". The idea here is that I would recommend abstracting a lot of treasures out into single items.
For example, when the party defeat a band of goblins, the DM should first present them with the list of gear the goblins have. If the PCs want to equip any of these items individually, they are free to do so. However, whatever is left is then considered to be wrapped up and turned into a single (major) item called a "bundle of XX loot". Such items cannot then be unbundled (since we're not tracking what they are individually), but can be resold at town for a fixed amount.
This saves micromanaging the details of everything a random bandit has (and especially the small amounts of coin/gold teeth/minor trinkets they might have).
You could have a "bundle of poor loot", a "bundle of average loot", a "bundle of good loot", and so on, right up to "a bundle of priceless loot". (In each case, the bundle should consist of stuff that isn't good enough for the PCs to bother using, but good enough for them to want to sell on.
Similarly, with coins, I would go with "a pile of poor coins" (mostly copper with some silver) up to "a pile of priceless coins" (mostly platinum with just a few gold). A pile is about 3,000 coins (or set accordingly), but the exact number is handwaved - it's not as if the party is going to rigorously catalogue this in the middle of the dungeon anyway, is it?
And the same can be done with gems.
The idea here is to reduce the book-keeping of mundane treasures, and avoid overloading the encumberance system with detail (while still not allowing PCs to carry absurd amounts of loot everywhere).
