one would suggest this is a mod for the throttle response from the pedal input.
you can modify the output to the throttle body so that with the slighest bit of pedal input the throttle body flies wide open, giving you a seriously aggressive throttle response, otherwise known as sport mode. adaptive parameters should to a certain extent allow this, my GTA seemed to behave this way. if you really started to drive it like a complete heratic it would bite your head off and response really aggressively. I would think that this pedal mod takes these adapative parameter settings 'to the next level'
normal will just be as standard.
ECO is most likely a reduced throttle response so that you cant achieve full throttle so quickly and easily therefore having a less aggressive response and so use less fuel as your not able to drive the car so hard.
I would think thats how it goes anyway.