crafting is pretty borked. for the last week or so I have been trying all the strategies, watching colours, rotating through standard, rapid, bold, wait, and have been succeeding more than failing, but not great results.
Today, however, I needed to clear out inventory, so thought I would craft all these mats down that I have been saving. And really there was a lot, so I didn't care about succeeding, I just wanted to clear inventory and get a few skill points if I could. So I have been spamming Rapid all day, not looking at colours, I just wanted to get through this as fast and painless as possible. I haven;t failed a synth yet today >< AND now I'm getting rid of weaver stuff, so I was synthing recipe's 5 levels higher than me (yarn says 11, I was 6 when I started on them) didn't fail a single one spamming rapid. So crafting is just borked, there is no rhyme or reason to it yet.
So until I see patch notes talking about crafting, Rapid all the way. Just be careful not to power click like me right into "touch up" and have it botch on that :P