Expectations

[Davin]

Agreed, Grim.  I should have thought to mention that myself, as it's also a major factor deriving from the time between turns.  In this age of instant gratification in most game play, PBM-style games (even without true postal delivery) stand out for generating that escalating level of tension every turn that you really don't get anywhere else.  (Of course, that's what inspired your magazine title of "Suspense & Decision".)