I was reviewing recent pro games on go4go.net, and noticed a few things. First, the avalanche joseki seems to have come back into fashion. Second, the vast, vast majority of recent games I reviewed where the avalanche was played ended in resignation.

Reasons why this might be:

- There are new variations being played, which haven't yet totally been worked out, giving one side an advantage.
- Go players who play avalanche are the fighting sort, and their games tend to end in resignation anyway.
- I am just looking at too small of a sample for this observation to have real meaning.

What else? Has any research been done on the topic of joseki/fuseki choice and probability of resignation?

I don't think studying avalanche is healthy for us amateurs

Like you I can really only speak in terms of impressions. However, through compiling GoGoD I see data for more games than most people and I also used to collect Avalanche games (had well over 1,000 plus very many articles), not to mention I translated the extremely good Superbook on this opening (not available now, don't ask).

Decide for yourself if my impressions are more likely to be reliable, but I would say:

1. Avalanche games do not generally lead to more resignations than other openings. Bear in mind that not every Avalanche leads to long running battles.

2. The increased number of resignations one sees nowadays is mostly a result of Mickey Mouse time limits introduced for tv games, plus perhaps a strong disinclination to count up, maybe because tv producers don't like it.

3. The Avalanche joseki has never gone out of fashion, though it does tend to be avoided in major games (but not by major players). It is often reported as one of the topics being studied in pro study groups.

4. It does seem significantly more popular than the Magic Sword.

Pros sometimes resign when losing by half a point in the late yose, so I wouldn't read much into the prevalence of resignations (unless you actually check the resigns are from big fighty deaths).

When Michael Redmond visited the UK 2 years ago he said the avalanche had somewhat gone out of fashion in Japan, the general consensus was it was a little advantageous for the player in the corner.

One thing I've noticed (and maybe read about) is the outside player pretty much always plays the outside extension on the 3rd line now as the opponent's shape is too good if they get to atari there (f17 in http://www.go4go.net/go/games/sgfview/45736). This gives the trade option in which the approacher gets the corner which, locally is a tiny bit better for the initial corner player but the direction makes it even on most boards the avalanche is played. Also I'm seeing that d11 push a lot in games recently. And there are new variations being explored, such as this crazy fight: http://www.go4go.net/go/games/sgfview/42952 (r13 at o13 was the normal move before).

If you first learn the avalanche joseki from a traditional source such as Ishida Yoshio's book, the new variations in recent professional games are beyond recognition.

I would think the opposite. Aren't there a lot of shape issues in the avalanche? like you can learn why the wrong moves are wrong and how to exploit things and whatever.