No. Masterworks represent an investment of labor by a highly skilled dwarf as opposed to the same investment of labor by an unskilled dwarf. Skilled dwarves are rarer. Masterworks are subjectively more pleasing, and objectively superior in combat. This alone is sufficient to give masterworks a higher price.
As I said before, masterworks are higher in eliminative value, which means that if you want 10 chairs and you have an option between 10 ordinary chairs and 10 masterwork chairs, the ordinary chairs cannot be sold but there is no difference in the value of the masterwork chairs and what the ordinary chairs would be worth if they were around. This however is not the kind of value that factors into prices, it is the kind of value that determines whether something can be sold at all.
A highly skilled dwarf is objectively cheaper than the less skilled dwarf. That is because he makes fewer mistakes and wastes fewer raw materials in producing things. On his own a highly skilled dwarf might produce more value, but he reduces the average value of each item he is employed in making, which means he only produces more value if he is *more* skilled than the other dwarves in the world. Increasing the total skill-base of the whole economy does nothing to increase the numerical value of the items produced.
It does however increase both the eliminative and binary values, which means people are certainly better off than they would be otherwise. But the numerical values and therefore the prices of the items goes down, because as the more skilled dwarves produce more goods more quickly, the amount of labour that each item represents goes down. The more skilled the labourers are therefore, the lower the prices ought to be but under the current system the reverse would be the case.
Value is not the same thing as price however. Price is normally higher than value, this extra in effect a % of the total amount of surplus value produced by the society. Surplus value is the difference between the value of the goods produced by each dwarf and the value of the goods that said dwarf consumes; at the moment this is a pretty large difference. You can raise an item's price above it's value but only if there is surplus value leftover in society.
The time/labor costs of an item's production are largely irrelevant to a buyer, and should therefore have no impact on the item's price. Where they are relevant is on the artisan's desire to produce that item: Things that take a long time to make but give only a small return simply aren't worth the maker's time, so of course he chooses not to make them, which creates scarcity, which drives the price up, which makes the item worth making. But in DF, there are three things that break this natural equilibrium: 1) Dwarves don't make capitalisitic decisions in a communist society, 2) Dwarves have no qualms about doing non-cost-effective work, especially when there is often literally nothing else to do, and 3) Legendaries can and will do the same job in the blink of an eye, effectively making the entire concepts of "labor costs" and "competition" obsolete.
Suggested improvements:
More realistic timeframes, for all products. No Mason, no matter how Legendary, should be able to whip out 15 stone weapon racks in an hour--just as no Cook, no matter how Dabbling, should take 3 days just to prepare some stew.
Smaller speed increases as an artisan gains ranks in a skill . . . perhaps even none at all.
Revamp the creation process into a multi-step one, rolling the "quality dice" each time. As the craftsdwarf completes an item, he compares: 1) The time he's taken on it so far, vs. the "average" time for that type of item, 2) The quality level of the item, vs. his own level of skill, 3) The quality level of the item, vs. the odds that any further work would be an improvement, and 4) The time required for further work, vs. his own needs for food/drink/sleep. IF the craftsdwarf is a) not too far behind schedule, b) unsatisfied with his work so far, c) fairly sure that he could do better, and d) not too distracted by physical needs, then he should try to fine-tune and/or salvage his work. Roll the quality dice again, and maybe he'll improve the item, maybe he'll make it worse, and maybe he'll screw up completely & wreck it beyond repair. So the main reason that Legendaries can do work so much faster than other artisans should be because they got it right the first time.
In what strange universe does the buyer solely determine the price of an item? Prices are ultimately set by the seller, which means that in no sense can the costs to the seller be rationally ignored. A seller will always try to avoid selling an item at a lower price than he acquired it for. If you follow the chain of costs down to the bottom, what we end up with is the limited number of work-hours that the worker has.
Your entire setup makes no attempt to establish the basis for the value of anything, it just takes the values of things a-priori to exist and then tries to control people's behavior according to these tautological item-values that somehow everyone both knows and have quantified prior to any actual economic activity.
Then you say this.
True. I never meant my post to be a correction of yours, merely an expansion. And obviously, yes, the current in-fort economy (or rather, total lack thereof) is only a placeholder.
The situation where items have in-built values is also a placeholder surely?