In a nutshell, one of the main purposes of “Desynthesis” (abbr desyn) is to obtain the new i95 crafted primal/mog weapons, which are meldable, and probably HQ-able (HQ stats are better than what you see on the marketboard). If you already have Animus weapon, or even better, a fully melded Novus weapon, you may not care about it at all, and you may skip the rest of this discussion.
In summary, desynthesis is something you can learn at lvl 30 as a crafter. It breaks down a gear (NOT a mat! E.g. NOT iron ingot, NOT rose gold nugget) or a weapon/tool into some of its original mats. Each person can have only 300 points to be shared among all crafting classes, so theoretically you may have 3 classes at 100 points (max), but in reality, only 2 (due to the mechanics of how points are gained or lost).
Now, let’s work backwards. Each of the new i95 weapon recipes requires x3 “Demimateria of the Inferno”, 3x “Demimateria of the Vortex” or 3x Demimog Demimateria". To obtain these demimateria, one must use desyn on the OLD primal/mog weapons. However, since those old weap are UNTRADABLE, you cannot hand it to another person to desyn for you. You have to DIY (Do It Yourself)! Yet, even for an experienced crafter, we can only have 2 classes specialized for desyn. Therefore making it extremely difficult to acquire the demimateria. Furthermore, even if you successfully desyn a primal/mog weapon, we still dunno if it's 100% chance that u would get the demimateria, and I don’t know how many demimateria you can obtain from 1 desyn. However, once successfully obtained, the demimateria is tradable. Same goes for the new i95 crafted weapons. Not only are they tradable, they are also meldable, thus a fully melded i95 weapon will be close to the powers of an i100 weapon.
This harsh requirement of OWNING an untradeable primal/mog weapon, and having the ability to desyn it properly obviously is S-E newest attempt to COMBINE DUNGEON WITH CRAFTING. Hardcore crafters are forced to run primal trials to obtain those weapons, and hardcore raiders are forced to level crafting to desyn their looted weapons. This is why instead of putting this “Desyn thread” into the Crafting & Gathering Section.
The primal/mog demimateria are already available on my server for 1.5 million gil each. And u need 3 of them plus some more precious items to craft the new weapons... Currently, very few people are capable of crafting HQ 3 star items at high success rate, especially if HQ mats are not available for the craft (which is the very case here with these i95 weapons). So make sure u find the best crafter on the server to do this... Failing to HQ it would be a gigantic waste of precious mats, gil and effort. And total loss of mats would be equal to over 7 million gil loss. Although, since there are new crafting main tools available now in this Patch 2.3, I suspect 3 star crafting is going to be having much higher fidelity very soon.
Suggestion to players:
For those crafters who are interested in getting these weapons at a lower price, here is what I will suggest. Instead of rushing to train for desyn, you should first aim at obtaining the old primal/mog weapons. This can be done by running the dungeon, or simply by QUICK EXPLORATION from your retainer. The drop rate for primal/mog weapon is like 1/30 or 1/40. But it works, especially if you have 4 retainers.
For those raiders who are thinking about desyn-ing all your gathered primal/mog weapons, you might wanna think twice. Even though theoretically, you just need a single level 30 crafting class to learn desyn, a single level 30 crafting class is going to be very hard to achieve 100 points of desyn due to the lack of crafting powers. You may end up having to buy a lot of expensive gear for desyn because your crafting class is too low, and you can’t make them. You might as well just buy the demimateria or the weapon.