In tonight's lesson in the Go7 club in Vienna, Kobayashi Chizu-sensei reviewed a pro game where such an eye-stealing tesuji was played and said it was called "katachi wo kuzusu" (if I understood correctly) - she translated it as "taking off the shape". I've searched for this term and found that it might be "形を崩す", where "形" is "katachi" (shape) and "崩す" is "kuzusu" (destroy).

Can someone shed more light on this term? I've never heard it before. Is "eye-stealing tesuji" the equivalent, or does "katachi wo kuzusu" encompass more?

Thanks.