Lev, this was a part of your article :
Quote:Chapter 1: History
The Euwe Defense to the Blackmar- Diemer Gambit is a solid, yet very passive
set-up. It was originally recommended by former World Champion (1935-1937) Dr. Max
Euwe in 1950/1951 in the German chess press. Euwe’s original line ran 1 d4 d5 2 e4
de4 3 Nc3 Nf6 4 f3 ef3 5 Nxf3 e6 (Euwe Defense). Diemer continued 6 Bg5 here,
pinning the Knight to the Queen. Now, here Dr. Euwe originally suggested 6...c5?!.
This was refuted brilliantly by
7 Bxf6! Qxf6 8 Bb5+ c6 9 00! with advantage to White. The point is that after
9...cb5 10 Ne5! leaves White with a crushing attack and a lead in development. Thus,
it was not long before improvements were found for the Black side.
But like in usual, you put illegal moves in your analysis : after 6..c5 7.Bxf6 Qxf6 8.Bb5+ c6 is impossible, and cxb5 also

But because I have a good knowledge of the BDG theory, I know that the variation you gave works against 6..h6? 7.Bxf6! Qxf6 8.Bb5+ c6 9.0-0 cxb5 10.Ne5 and White get a winning attack.
The same idea against 6..c5 can be played, but that far from convincing. For example 6..c5 7.Bxf6 Qxf6 8.Bb5+ Bd7 9.0-0 cxd4 10.Ne4 Qg6!? (there is a game from 1990, Leisebein-Papenbrock, 0-1 in 43 moves) and 10.Nxd4 Qe5!? are not that convincing for White. So, I don't think that 6..c5 is refuted.
It's not the first time you do that type of error Lev (impossible moves or wrong variation), and it was in a published article, you should reread what you write, it's a subject that you should know too good to make mistakes likes this and like in the other thread about BDG move order!