This can probably be played with a different configuration on the left side, however in the Kajiwara games in my database it was this formation. This is mentioned in Reducing Territorial Frameworks (by Fujisawa Hideyuki) and occurs in several games of mainly Kajiwara Takeo.
As always with probes timing is everything, this probe only works accordingly (to my understanding) if it is played before there is more action on the rest of the board, so White can still adapt to the answer Black gives.
(Dieter: Several things come to mind when I see . First thing is: DDK at work. Oh, it's Kajiwara. Then second thought is: don't try this at home. Third is: what would Go Seigen think of this? So I went into gobase and found no such pro game. Kajiwara on a vanity roll?)
tapir: Well, most probes professionals do play look absolutely awkward to players like me before learning about them (try to play in good style, but sometimes with doubtful reading). Like: What? How can you play there? Isn't that premature? The problem is for me I used to think only about clear moves - invasion, reduction, approach, enclosure (I don't play wedges very often.). The whole concept of probes that actively create aims for later is rather difficult to grasp in applied practice and highly sensitive to timing (say if any moves on the bottom side are already played). They are moves amateurs of my level rarely play and when confronted with too often choose the "strongest resistance/maximum profit" line without sufficient reading. In the professional games in MasterGo (4 by Kajiwara, who went 2:2 with it and one Chinese game) the opponents always connected against the peep, in amateur practice I bet you will see the third variation >50% of the time. But I don't see what could go horribly wrong here (you need to know a follow up against a Black pincer when you tenuki on the third, that is about all), I will certainly try this.
Bob McGuigan: I remember seeing this probe in connection with White's jump out at in the following diagram. I changed the upper left corner stone's position to make the jump more appealing.
has aji that would help White in managing the right side.
Dieter: looks like a violation of the principle to play away from strong stones. In other circumstances, the black string can be considered heavy, in which case
is a perfect attack, playing at the centre of three stones, but not yet. I would understand a move at a instead of
, but still it appears to me that White is throwing away options more than reducing Black's.
tapir: I don't find examples for this , which doesn't necessarily mean anything. I would wonder what
achieves here. Reasoning: With
in place before
,
would still be answered at
. So it isn't entirely clear what
achieved here. As opposed to that playing it directly after the approach / extend poses Black a question to the answer of which White can adapt = it is a probe. With
already in place
is the only obvious answer to the peep, so it isn't much of a probe under this circumstances, it might be kikashi / aji-keshi, but it surely isn't a probe anymore. Does this make sense?