Construction & Research under one subskill

[phunqe]

Slots are random, so having 400 Construction or 4 doesn't matter at all.

Do you have an official source you can quote on that?
I know a lot of tests has been done, but there were also tests that were inconclusive.
An official word on this would clearly be appreciated

Reason why is I'd like to know is if the following is then outdated/false (in which case it should be removed):

Besides slotenhancers, which guarantee 1 to 3 slots, the only way to influence your chance to get slots is to get a construction skill as high as possible.

There are 2 variables in the formula that determines the amount of slots: the quality of the built item and a random number (0-199). Although quality of constructed items has a cap, the quality used by the formula is the theoretical quality, so having just enough CST to reach the build cap for the desired item is far from being optimal. In fact, if the quality is below a certain level, it is not possible to get 5 or even 4 slots. This quality is based on the TL of the constructed item DEX, INT and your CST skill.

So having a high build quality opens up the possibilities to get up to 5 slots. To get the slots, a random number is rolled. If that random number is above a certain number (derived from fixed factors and also the quality), you get 0 slots. For 1 slots, the random number has to be lower than the calculated number above. For 2 slots, it has to be below another number that's lower than that required for 1 slot. Same thing for 3, 4, 5 slots, the random number the game rolls has to be lower and lower. That's why builds with low quality can never get 5 slots, the required number would have to be negative (which it can't be).

As the quality factors into the formula determining the breakpoints for x slots, a high quality means a bigger range of random numbers will be able to get you slots. In other words, it increases your chances to get slots.

Rare weapons are a special case though. In addition to the formula described above, there is another roll for either 0, 1 or 2 additional slots (33.33% chance to get either). That's why rare weapons generally have more slots than non-rares.