I have always hated the Vienna defense since black is always able to exchange some pieces and thus reduce white's winning chances. I always felt that white is fighting for a draw.
For that reason, I have worked in the past on several white options, originating aftre 5.g4 Bg6 6.g5 Nd5 7.Nxe4. Not without any modesty on my part, the line 7...Nc6 8.c4 was dubbed the "De Bouver attack" and yielded terrible complications.
However, black could bypass this dreaded attack and simply play 7...e6 and now 8.h4 does not seem to equalize.
That's why I look today at the next white option : the "More than Hara Kiri" line, originating after 1.d4 d5 2.e4 dxe4 3.Nc3 Nf6 4.f3 Bf5 5.g4 Bg6 6.h4 (diagram)
White's most ambituous try is probably 6...Qd6, but white's reply 7.Bg2 is both unexpected and good.
Also interesting is 6...exf3 7.Qxf3 and white gets an equal game with all pieces still on the board.
The popular 6...h5 is rather simple to play for white after 7.g5 Nd5 8.Nxe4 (diagram) and white is certainly not worse than in the lines without the h4 moves.
Let's look now at the best black repsonse, 6...h6. Scheerer suggests 7.Bg2 here, but I think he overlooked the simple 7...Nc6, leaving white a pawn down without any compensation.
Summary : the More than Hara Kiri line seems to be refuted by the simple 6...h6 as Scheerer's suggestion 7. Bg2 does not provide any equality.