Just taken a brief look at that link. It's no wonder Wikileaks doesn't endear itself to many.
That said, I suppose in reality it's just a more in-your-face presentation of what's already in many organic chemistry textbook in any number of libraries.
Frankly, I reckon there's little that can be done to stop the illicit manufacture of these drugs for the logical reason that they're such simple molecules. Many are just minor variations on the basic d-enantiomer (dexamphetamine) which essentially is only a benzene ring with a single branch containing a CH3 methyl and a NH2 amine group. So it stands to reason that there are many comparatively simple ways to synthesize them and that more are likely to be found. Moreover, the more precursors there are, the harder it becomes to ban them all, as eventually we'll hit the point where certain precursors are too ubiquitous and or important to ban.
It seems to me that if we're to take harm minimization seriously then we need to take a more sophisticated approach. For staters, we need much more efficient public health measures to detect and separate out genuine self-medicatiors from the partygoers who take illicit drugs.
As we know, these sympathomimetic amines have been prescribed by the medical profession for decades for certain depressive illnesses, ADHD, etc., but because of their their potential for abuse - not to mention certain moralistic attitudes among many politicians - these drugs have a horrible stigma attached to them and that has stopped many undiagnosed people from being prescribed them legally. The consequence is that many of them self-medicate with illegal drugs and the outcomes are often dire.
I think that taking a serious approach to medicalizing the problem would help very significantly. This would also include distinguishing the amines from the opiates. Whilst the medical profession understands fundamental difference between these two classes of drugs, public policy often doesn't and the drug problem ends up as an amorphous mess that becomes even harder to sort out than it otherwise would have been.
Therefore, there needs to be a more nuanced and sophisticated understanding amongst the general community to the effect that someone who turns to illicit amines is likely doing so for fundamentally different reasons to another who has turned to opiates. A more sophisticated approach to the drug problem would lead to better outcomes for not only those addicted to drugs but also for society in general.