Hasty hand wont work well if you have the level of the craft you do. And I was not talking at all about doing all the crafts at once.
No XP sounds extreme, but i like the idea. I would go with as low as 50% xp off. I also like the idea of the "3 in 1" principle being extended.
Again, i'm not talking about HQ here, but crafting large number of items in a less boring and repetitive way.
I have not played that game a lot and in no way use it as a model.
I'm not using the "little time" as an absolute excuse. If each synth takes you 2 minutes and you have 50 synths to do, i wouldnt mind the auto-craft option to last for 1h40. But i would use those 1h40 to do something else than pressing enter wether it is on "standard work" or "hasty hand".
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Now look people, this is the system as it is now :
>open synth window
>select mats, select the tool
>item window opens, clic confirm
>craft your item, it is now in the reciepe list
>finish craft, you are back to the synth window
>clic reciepe, reciepe window opens
>select the reciepe you want, clic confirm
>back on the synth window, select the tool
>craft the same item as before
These are an awful lot of steps for crafting the same item twice when you firstly dont know the reciepe. I propose :
>open synth window
>select mats, select the tool
>select the item you want to craft with selected mats
>clic a checkbox "do this reciepe mutiple times"
>craft your item, synthesis ends
>instead of going back to the synth window, synthesis starts again (0% progress, 100 durability)
seriously, is that too much to ask ?

would save plenty of time while not ruining FFXIV idea of crafting, am i right ?