Your panel puts out 4.4 amps. That 18 watts is not going anywhere, it's just not being produced because there is a poor match between the panel and the battery. If you have a cloudy day, or the temperature is high, you don't get 17 volts. At the temperatures seen in many hot climate areas, you might get 15 volts. The panel will just sit there looking dumb, and your batteries will get even stupider than usual.
Nobody likes a stupid battery.
Panel tracking - this is where the panels are on a mount that follows the sun. The most common is the Zomeworks. These optimize output by keeping the panels very close to 90 degrees angle for maximum sunlight. Note that this is just the opposite of the MPPT, described below. Maximum power point tracking - this is electronic tracking, and has nothing to do with moving the panels.