Page 64 of the 2000xl manual
Auto step increment:
After entering data in step input, you can automatically move a sequence according to the
value set in the Timing: field on the main screen each time an event is entered from a
pad or MIDI keyboard.
Setting this to YES will move the sequence according to the settings in the Timing: field
after the drum pad or MIDI keyboard has been released (and the note off has been sent).
In Step Edit mode once you enter a note the screen will jump to the next song position pre determine by the timing field
It just saves you the extra step of advancing to the next time field
