cross-cut, diagonal away
After a cross-cut in the centre of the board, isn't a recognised good shape. One can give some reasons.
Supposing Black simply answers with . Then this is similar to the position in diagonal play reference positions?: White is at some disadvantage for influence. You could also say that threatens a good play at a.
The same position arises here, though with Black to play. The 'correct' way to cut here is with at (strike at the waist of the knight's move).
Tapir: I disagree. 1 and 2 are both the "waist" of the keima - afaik. However, if 1 at 2, 2 at 1, 3 cuts at the point left to 1, than 4 can capture the cutting stone in a ladder. It may be bad shape, but here without any other stones, it is not the wrong cut, but the only one.
For all these reasons this is a relatively rare shape.
An example can be see at Attach-crosscut corner patterns, in the 4-4 point case.
Another is in this difficult joseki:
This was played by Shinohara Masami against Go Seigen in 1935; it is hard to know how current is.
This counter-example to the diagonal away move being a bad move has a reason. The main reason the diagonal move is bad is because on an open board after , the two black stones have bad shape, with a play at a a strong reason. However here a lies on the first line and so isn't a threat at all. Also, with a white stone bearing down, it is imperative that black can extend down along the side and for that reason must be preferred to b.