From: Adam Chalcraft <dac11 <at> PHOENIX <dot> CAMBRIDGE <dot> AC <dot> UK>
Date: 14 nov 1991
Subject: RE: Crimes against humanity

It's an edge play - i.e. a tesuji on files 1 or 9.
It involves getting the rook behind the lance,
for example P-1f, L-1g, R-1h.
The idea is to push through on the (here 1) file.
The square 1c is usually too heavily defended for this to work as stated,
because it has got a knight and a bishop on it at the start,
but you can bring up an extra knight or silver to help in the battle.