Anchor Set (アンカーセット)
A rarely used technique that is utilized to maintain Back-to-Back. Given its name because of how the J kind of looks like an anchor.
After anchoring a J, you stack up a donation Tetris. You do need to be conscious of how you stack, or else the open column underneath would remain covered.
Compare with how you would typically clean up the TST overhang by soft dropping and sliding in an L or a J. In contrast, notice how no soft drop was required in the above example involving Anchor Set.
Placing the J for Anchor Set, assuming that you intend to maintain Back-to-Back, effectively means that you will be committing to stacking 4 more lines to follow up with a Tetris. When you slide in an L, you only have to stack 3 more lines to follow up with a Tetris. This means that you'll remain vulnerable to attacks for a more extended period when you use Anchor Set in most cases.
- Tetrisch on Anchor Set