Belly attachment ladder breaker

White to move  

White would like to cut at A and save the big group at the top but will be caught in a ladder:

White to move  

If she connects with a plain table shape. Black can connect and capture the top.

The amazing move  

White has this amazin belly attachment as a double purpose move: it serves as a ladder breaker while it also enables a push through at A.

As a ladder breaker  

If blocks, then can cut because the ladder is broken: if Black A then White B makes 3 liberties against 2 for Black's cut off stones. If Black B then White A is next escaping or putting B in atari.

Push through  

If connects this time White can push through and either capture or capture 3 stones in a ladder.

Black's resistance  

Can Black also play a double purpose move like this one?

No, up to White B the black stones are caught in a loose ladder.