If your enemy is secure at all points, be prepared for him. If he is in superior strength, evade him. If your opponent is temperamental, seek to irritate him. Pretend to be weak, that he may grow arrogant. If he is taking his ease, give him no rest. If his forces are united, separate them. Attack him where he is unprepared, appear where you are not expected.
Know thine enemy as thyself, etc etc
Agree with you sir, in this type of game deception takes the form of the openly unknown and the openly unseen. Your play shows your intentions and what is possible, the surprise comes when your opponent STILL doesn’t “see it coming” over a period of some hours of play!
Chess is the same way. Nothing is truly hidden, and all you have each turn is 1 unit of fresh information to attempt to discern what your opponent is trying to do.
The best players of chess play it like poker; your opponents know your preferences and predilections and it is your job to lure them into the trap of assuming you will act in the same was as before, or the same way the last grandmaster did, or the same way they would.