Actually that question, while it may have been rhetorical, got me thinking.
The light source puzzle, at least in Zork, was twofold:
- It stopped players from wandering in the dark and possibly bypassing puzzles or getting lost permanently (especially with the trapdoor being barred)
- It imposed a timelimit on the game (number of turns until lantern popped out).
They did the same as #2 with the hunger puzzle in Sorcerer/Enchanter.
It seems like what these puzzles SHOULD be used as, whether they’re hunger, inventory, etc, is as a method of pacing the story.
The reason we stop them from carrying around everything is to slow them down- by forcing them to move through familiar areas. This might have the benefit of making the rooms more “memorable.” For example, I can now go thruogh Zork without a map, partially because you had to move through these rooms so often on the trek back to the trophy case. Likewise, I’m overly familiar with the carosel room in Zork 2, but not as much with the further away rooms, because that was a good “central” location to deposit goods. That made the need of the map a bit lesser as a consequence.
A light puzzle would be one of the tools used to keep people out of a given area until later in the game, or to put in a sense of “danger”. If your light could go out at any time, you’d better be very careful about what you do down there. However, if you have a permanent Frotz spell, then light is mostly irrelevant. In many ways, this is like a “need a key to get into a door” type thing, though there were nice light puzzles- (Such as the gas room in Zork, forcing you to go back to your lantern- hope it still works!, or using the grue repellent instead of light).
Secondary to these are actual inventory based PUZZLES, like the long slide in Sorcerer/Mainframe Zork or the Drafty Room in Zork I, where the puzzle was getting items into places when you COULDN’T carry them. Those I think were much better than arbitrary limits.
I think the main issue here is seperating the current IF game from the typical D&D Dungeon Crawl for the main purpose of gathering treasure items. In the latter case, encumbrance was much more of an issue to be overcome, where in the former, perhaps it shouldn’t be relevant.