Yesterday I reached rank 34 Leatherworking, when making fleece first comes available, so I thought I would give it a try.
I attempted this synth at ranks 32 and 33, and could not attempt, so it is definitely a rank 44 synthesis. (Also I received ~1500 xp for each synthesis, further confirming for me that it is +10 ranks)
I suppose by luck I happened upon the right configuration of stats, and was using a good set of crafting abilities (Mass Production, Fulfillment, Assemble, Ingenuity), but I successfully completed the synthesis 11 out of 11 times. I can understand luck allowing me to succeed once, or even twice but a 100% completion rate on 11 synths in row seems unlikely to attribute to the RNG gods.
Having said that, I then went and attempted white coral arrows (a rank 39 synthesis) at rank 30 carpentry, only to have a 50% success rate (two successes out of four). I attributed that to an incorrect balancing of my crafting attributes, and so will have to try and shift them around and see if I can't improve things.
I personally think that the crafting game does reward skill and a deeper understanding of what is going on. Although I don't claim to fully understand it, that is what keeps the crafting game interesting to me -- there is still more to learn. People over the Battle Mechanics section are complaining that battles are too easy. Please, please, please, SE, don't neuter the crafting system and make it "easy-mode".
