by dr Kromm (firstname.lastname@example.org)I've noticed some distinct confusion about what "initiative" means in GURPS. Here's the scoop:
"Initiative" is the advantage possessed by the side which gets first strike at the start of a small-unit engagement (pp. B122-123). An "initiative roll" determines which force gets the jump on the other, gaining a few "free" actions, and has nothing to do with the order in which characters act during an engagement in progress. This latter issue is one of "sequence" (p. B95), which determines the order in which characters on the side with initiative will take their free actions and, once surprise wears off, the order in which all characters on both sides will act.
The initiative system is a "war game-like" rule that is intended to cover situations where one force outfoxes the other, gets the jump and inflicts casualties freely; "a running man can slit a thousand throats" or however it goes. The sequence system is intended to cover pitched, stand-up fights where both sides know there's going to be a battle and close on one another in plain sight. A sequenced battle generally follows surprise if the side with initiative does not overcome its foes right away.
Combat Reflexes and Tactics skill help determine initiative because tactical surprise is an issue of troop quality (Combat Reflexes or not) and planning (Tactics skill), and applies to an entire force in combat. Move and Basic Speed help determine sequence because speed equals shock and flexibility in a fight in progress.