Wouldn't you be happier if B played as in the next diagram, leaving the weakness at 'a' ...?
As White yes, as black not. I dont quite get what your aiming at.
$$W Joseki continued
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- Click Here To Show Diagram Code
[go]$$W Joseki continued
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And a is a sente possibility to make the weakness dangerous. As in the game i already had a stone in that area it -
All this is not possible in your first diagram.
After looking at these josekis they dont look much different than what was played in the game- I guess there is some move order opportunity fo black to thwart this line, if white cuts at

first (like in game), but i would have to study that more. Also could be that it's just better in terms of ko threat usefullness.