I refer to the so-called Czech Benoni: 1.d4 Nf6 2.c4 c5 3.d5 e5 4.Nc3 d6 5.e4 Be7.
The line acquired its name after being developed and played a lot in the late 1960s by various Czech GMs, such as Hort, Jansa, Kavalek, etc. If you look at the early volumes of Informator, you will find quite a lot of games with it, and it was quite popular around the period 1968-72. But then it sunk back into relative oblivion, from which it has never fully recovered.
It is not everyone's cup of tea, of course - a blocked position, with less space, dreadful-looking bishop on e7, etc. Indeed, England no. 1 Mickey Adams is wont to say "It looks a bit Czech Benoni to me!", about any position that he doesn't think much of. One player who did make a determined attempt to revive the line was Tony Miles, always a connoisseur of offbeat and disreputable openings. He played it a number of times in the period 1986-90, but lost almost every time. After that, he dropped it for a while, before wheeling it out against Lautier in 1994. After getting another whopping, Miles quipped in the post-mortem that "I only play it once every four years or so, because it takes me that long to forget how bad it is!".
One player who did use it with great success was Bill Hartston, which probably explains my own fondness for it. The first chess magazines I ever saw were in 1973, when Hartston won the first of his two British Championships, and was clearly our number one player. He wrote an excellent chapter on it in his book on the Benoni.
Bill Hartston, apparently undecided on which colour to play (photo: tvcream.co.uk)
Is it so bad? I don't really think so. Black avoids exchanges, keeps a solid structure, and has various plans to untangle his pieces - Ne8, Bg5 (to exchange off the bad bishop), g6-Ng7 and organising f7-f5, possibly the queenside break b7-b5, etc. As I say, it is not everybody's cup of tea, but those who like long manoeuvering positions and a lack of hard theory, should find something to their taste here. At least it is not the sort of position that a computer can analyse out to a forced draw.
So, if I am so fond of it, how come I only ever played it once? I really don't know. It's not as if I lost - on the contrary, I won a model game from Black's viewpoint, eventually exchanging off all the bits, to reach a good knight v bad bishop ending, which the adjudicator settled in my favour (I'm sure I would have found the winning plan anyway...). But I never returned to it. Cynics would say I did well to quit while I was ahead. I'm not so sure.
Here's an example of what it can look like on a good day. The notes are from Megabase, where they are attributed to Hartston/Littlewood. I presume that is John Littlewood, although it is not made explicit.

