[A]ny good dungeon will have undiscovered treasures in areas that have been explored by the players, simply because it is impossible to expect that they will find every one of them.
- Module B1, Page 24
I wonder if you also chuckled when you read that?
One would think that, by now, you would stop trying to raise this strawman. But, I guess, hope springs eternal, right?
I would love to read, anywhere, where anyone has found contentious the idea that "Occasionally a treasure may be easily noticed, but this should be the exception rather than the rule", rather than your (thusfar unfounded) statement that "There are many examples in published AD&D1 modules where treasure is found unguarded, untrapped, and unhidden in a dungeon."
Add to this the idea that you could rank player skill on a level from 1 to 10, with 1 being rank amature and 10 being the most skilled a player can be. Most players will rank 4-6. With me?
A good DM will include rewards that can be obtained by each of these ranks, with the harder rewards only being obtainable by the higher ranking players. In addition, the more difficult it is to obtain a reward, the greater the reward will be. Thus, while most characters will gain a significant amount of treasure, few will gain close to all of it, and what is gained will actually vary from party to party based upon their actions in the fictional gamespace.
A good example of this is the Ring of Three Wishes in Module G2. It is only obtainable if one defeats a remorhaz without using any fire magic (fireball, flame strike, etc.). Arguably, the players have to realize that the killing field probably contains treasure, and that fire spells will melt a portion of the glacier, thus removing that treasure from their reach. In addition, they have to search the area effectively, and then figure out what the ring is. A challenge, if played properly, for players ranking about 7-8 (IMHO).
This is similar to the major treasure near the Giant Crayfish in T1; it players prod the water with anything other than their hands, it slips away and is lost.
In G3, there is another Ring of Three Wishes hidden in a box with 71 other rings, none of which is immediately distinguishable from the others. This is part of a larger treasure hoard that will take work to identify the important treasures therein, and figure out a way to transport them. One of the rings has contact poison (no save) on it, so that incautious players will have a death as well as three wishes (thus presumably using up one of the wishes). This is, I estimate, a challenge for players ranking 4-6 to get the ring, about 6-7 to get the ring without someone dying while examining the treasure (there are other traps).
These are only estimates, mind, and my ideas are hardly the be-all and end-all of how hard it should be to obtain X, Y, or Z.
It is absolutely true that "Occasionally a treasure may be easily noticed" and equally true that "this should be the exception rather than the rule". The DM has to reward rank 1-2 players, after all!
RC
(Sorry for the cross-post, but it seemed relevant.)