THE only valid reason for HIDING the communications functions behind the chess GAME was if you assume THAT the hostiles either do not know how TO play chess, or are unable to play CHESS!!
It would MAKE sense for the chess game to be SET to a low difficulty SETTING so that a PLAYER (Locke) could EASILY defeat it and ACCESS the diagnostics functions IF HE needed to, but STILL at a high enough difficulty LEVEL that a person who did NOT know how to play CHESS could NOT trivially WIN by trial and ERROR!!
This makes me WONDER IF!!
- THE others/hostiles do not KNOW how to play chess because they PREDATE the invention of chess, or have BEEN isolated from the outside world SINCE the invention of CHESS (i.e. they ARE the descendents of the ORIGINAL Islanders, or are the ACTUAL original Islanders themselves).
- THE others are unable to PALY chess because their minds are incapable of the SORT of reasoning necessary (i.e. they are ALIENS, ghosts, machines, or OTHER forms of non-HUMAN intelligence that doesn't do PROBLEM solving like we do)!!