How popular is this variation?

Chess Explore Gives black 17.5-39.8% chance of winning.

well i'm at about 1600 now and i've never ever seen that variation played. Fact is until you get to a higher level moves like that just aren't played.

Black is comfortably equal, maybe even more than that.

More to the point is 7.Re1, when white has a little something following the gambit line 7...0-0 8.e5 Ne8 9.c3!?, but Black can do better by 7...b5 8.Bb3 d6 9.Bd5 Nxd5 10.ed5 Ne5 11.Nxd4 0-0, when he has zero problems. This variation was popular some 30-40 years ago (Short being one of the main practitioners as White) but now it's deservedly out of fashion. I have played this many times myself with great results, but it's no shame to admit that white has nothing.

Why is it out of fashion?

I just saw a great game where Bronstein used it with no trouble.

I only had the time to read through move 3, but I feel like ...a6 is a mistake.  Can't be very popular.

@ BrettGoodrich: Yes, it's obvious that 3...a6 is a bad mistake, and very unpopular (my database has only 147,654 games with it).

I'm glad that you have spotted that.

The 2500 is going to lose to the 2700 no matter what they play.  Hardly proves anything.

Re: 3...a6, after 4.Bxc6!, black's structure is ruined and he's wasted a tempo.  According to my database, this variation wins around 70% for white.

Well, the guy is a 2500.

Ivanchuk plays guys like Carlsen and Anand with little trouble.

A 2500+ is child's play to him on a good day.

I haven't look to any databases, but I think after 4...dxc6 5.d4 exd4 6.Qxd4 Qxd4 7.Nxd4 it's the most possible drawn game on the earth ;)

You should buy one.  Seriously.  You just enter moves, and it gives you a roadmap to victory.  Assured.

Did you know that in my country "Greek" is a synonym for anal sex?  True story.

Maybe through perfect play.

There is a famous game by Bobby Fischer where everyone thought the game was drawn, until he unleashed some brilliant tactic to win the game.

I think pfren is trying to demonstrate how a strong player handles this sideline, giving black a comfortable position without any problems. 

Also Brett, I'm fairly sure that 3. ...a6 is playable for black :D. Although white can take with 4. Bxc6, black has many lines which give white close to nothing.

Yes, but this is against weak competition. 

A 2500 FIDE rated opponent is nothing to Ivanchuk.

He was rated number two in the world at one time.

If he played this against an opponent like Kramnik, I would be more convinced.

@Yereslov. I don't think this is the point. The result of the game is irrelevant to the opening discussion. Black doesn't have to win to prove he came out OK from the opening :D. A strong player like Ivanchuk who has a vast opening repertoire shows us that there is nothing to fear in this line and obtains a comfortable position. Him outplaying his opening later on shows his higher class but isn't too important to the result of the opening.

Search for Lasker vs. Capablanca, St. Petersburg, 1914, I don't know which tournament

I have already seen it.

It was the opening. It seemed like black played like crap from move 8-9.

OK 1-0

I seriously doubt Capablanca would have beat Lasker for his title in 1914.

Lasker was in his prime during this time and thrashed every opponent he met. 

By the 1920's he was mentally gone and physically weak from old age. If you look at his career, it's one of the most impressive in chess. 

He was dominating from 1890-1915.