Almar;
The link you posted http://pyrotechnic.narod.ru/Black_Powder.pdf I read in the last couple of years. The good thing is, the guy has a lot of good information, but the bad thing is, the guy has a lot of good information. haha
He can confuse a person about as much as he can help you not be confused. I guess one of the reasons, he is based in Pyrotechnics and maybe not so much in shooting. All in all it's a good read, but there is a LOT of information to digest in that article.