First of all methamphetamine is not 4-meth. I don't know what you mean here. Could you be thinking of 4-MAR?
Secondly, many of the people on this board, although not involved in producing, nevertheless
DO understand how meth is made.
You are correct in saying meth can be made from pseudoephedrine, but little if any locally made meth is made via the method you mention.
A similar method involves hypophosphorous acid, and this has without doubt been the method of choice for most Aussie cooks. Why?
Availability of the reactants
With the shortage of pseudo today, it's not unheard of for speed dealers to be also selling the acid. Where the acid originates from I would rather not say, only to mention it is made from
very easy to get materials.
Although your article suggests using red phosphorous from match boxes, the content of phosphorus has been reduced dramatically with the sparing coating that each box is currently given. Someone may do it once, but I would find it hard to believe anyone would do this regularly, especially when yields are general way lower than with the hypo method.
In reality meth can be made from many things, largely depending upon available resources and competence of the cook.
It will be interesting to see what will happen when these big syndicates are completely broken up. 20 years ago it could well be expected that this would limit meth availability. However with the vast internet resources on hand today, I would guess that many smaller producers will pop up. I have heard it said that some groups are making their own due to fluctuating supplies. Imagine how hard those would be to catch, when their product is only spread between a half dozen friends. I can’t really see this as being better for the health of users generally, but you never know. More care goes into home cooking after all
You can't go past
Rhodium if you want to read of reliable and proven methods of drug manufacture.