An 'investing' technique where you save the T shape underneath the T-spin. Translated into English, the term means Cut Copy. The setup is also called 千鳥格子 (pronounced as chidori goushi), meaning "a thousand birds grid", whose shape is like this: http://mathnokai.up.n.seesaa.net/mathnokai/image/chidori_memo1.jpg

http://harddrop.com/fumen/?v110@JeA3obA3kbF3ibH3gbF3pbA4G7eIjSBUbBdKcF8csQ?BSZBdAcFcBAAA

http://harddrop.com/fumen/?v110@neB3gbG3pbDUI7eAiaBZeD3lbD3zbAAA7eBAAAkSB/?dB3nbB3PcAAAFeD3mbC3HcAAA7eE92clWBNAdFgBAAA

• This variation of the first setup above requires a deeper hole and involves a line clear, but uses S and Z rather than 2 Zs.