It states that any row or column must add up to 21 (1+2+3+4+5+6) and therefore conclusions can be drawn from the overlap of cages.
Documentation to follow
Article created on 21-April-2011. Views: 8089 This page was last modified on 21-April-2011. All text is copyright and for personal use only but may be reproduced with the permission of the author.
Copyright Andrew Stuart @ Syndicated Puzzles Inc, 2011