[bitter&twisted]

"If you play such that your cards are obvious, it allows them to play optimally against you (if they're capable of that). "

Sklansky talks about this in the ""Mistakes" according to the Fundamental theorem of poker" section.

General idea "I think" is that the closer you play to optimally the more you gain/they lose, and the further they play from optimally the more they lose/you gain.

So yes when you play optimally you become obvious therefore it is easy for your oponent to play close to optimally.

So you use deception to try and get your opponent to play as far from optimal as possible, while at the same time trying to keep your play as close to optimal as possible.