Road Front Derailleur / Shifter Tuning
The two clicks are just one shift. You can do a half shift from the big ring to the small ring by pressing the downshift paddle about halfway. This is to keep the chain from rubbing when you are in a low gear in the back and the big gear in the front. This half shift is known as "trim". So two clicks up for a full shift into the big ring, two clicks down for a full shift into the small ring, one click down to trim the derailleur away from the chain when you're using gear extremes (big-big).