3-4 point low approach two space extension
in response to is a slow but steady move. White may choose this joseki if the position on the top side merits such a low and solid position.
It's a mistake for White to counter-atari with 8 -- White's shape get split.
Instead of a in previous diagram, and cut through with better shape. After and capture a stone, keeps the two White stones in check.
Zbaduk thinks that is a little submissive, compared to previous diagram. For Black, playing a after is not urgent. White has already been forced into a low position and Black's stones may be considered forcing moves In the opening stage tenuki might be more valuable than reinforcing here.
This appeared in the 1977 Kisei match between Fujisawa Shuko (Black) and Hashimoto Utaro (White), both 9-dan professionals. invades the high Chinese opening, and invades the White upper left corner in a tit-for-tat response. Owing to the very strong Black influence in the lower left, chooses the two-space extension over attacking by the diagonal attachment at a or even the more conservative small knight's move at b.