Ok, like i said maya has NO unit that is there's no unit just numbers (hard concept but yes it pure math it dont need units just numbers).
A bit of speculation that may help you understand: What seems to have happened is that the original maya had no units. So eventually you will encounter a poor sod who doesnt understand what a unit really is (not so hard if you have more than 1 client then youll have one, this is a problem of how the education works versus how human brains ascertain importance to things). So to avoid problems what they did was they added this later to appease the crowds.
Now units is not something you can really add later, it goes into the very core of your solver or not. But if it goes there then youll be paying a penalty every time you calculate anything. So allocation for units is a burden if implemented properly. The alternative way to handle units is to conform them to some other unit, this however has a number of problems such as having a bit of scaling problems (try using astronomical units converted to cm and back and you really fast get big rounding errors)
So to do units properly, you need to
1) have every numeric cell take in units, and then either conform or conform at next time its needed, later is better but needs much better coders to mange.
2) If you confirm then 2 values base unit to accept and unit to conform to, otherwise things can go unimaginably wrong
3) ALL things in the gui MUST follow the same convention
4) Your data needs to be somehow meaningfully anchored to physical reality (thats why things such as DPI have no meaning inside the computer, its only ever useful when you output a physical copy)
Now maya has none of the requirements. But it does not matter only very few persons would ever notice and of thiose only 10% would ever figure out why, especially since it would never matter one way or another. Unless you assume you know what a unit is, but use the definition you learned at school.
That is they changed the social aspect not the engineering one, a very good piece of engineering that is until it goes and breaks your understanding totally
Which one is it?
neither, one and both. See what they added was a option for units in prefs, but see it does not do anything because number requirement 3 does not come to play. Worse, the person who solved this wasnt actually doing a good job, he missed one critical part. See if units were to be something then youd expect the only module that has any sane physical anchor to match (rule 4), but they it does not. See what they missed is that the dynamic module had set gravity as 9.81 by default. This "screams the unit is a meter".
So what is the unit? the answer is NONE, no unit just numbers.
This means its whatever the hell you want it to be, and since some units try to understand units (ah they tried to engineer it in, but didnt succeed), that means it better not to change the prefs. But most things assume the unit is one meter, even if the prefs say centimeter. Since all assume otherwise then the prefs are wrong, ignore completely. In fact changing units is a disaster that you should avoid. But by luck its a computer application it does not matter only numbers and whatever you set as physical constants matter, est is just informing your users opf what you think it is.
