Wow, I hardly know where to begin.
"The Trackers on the link are single axis trackers that keep the panels perpendicular to the sun in the X and Y planes all day long, resulting in the most power harvested."
This is only true at the equinoxes (like today) when the plane of the panels are parallel to the rotation axis. It's the autumnal equinox for me - southern hemisphere. As the solar declination changes from today's zero degrees, the tracking error increases in both X and Y. We seem to agree here.
"The seasonal adjustment is raising or lowering the north or south mounting, ONLY."
WRONG! A polar axis tracker has to be maintained parallel to the earths rotational axis at all times. In tracking, we are trying to compensate for the earth's rotation to point to a fixed point on the celestial sphere. If you change the axis parallelism additional errors occur. Do the geometry to see it.
To correct for changes in solar declination throughout the year, the plane of the panels must be changed relative to the rotation axis to match the solar declination, but the rotational axis must remain constant.
"So-called "polar" trackers are actually aligned to a perpendicular to the ecliptic ..."
As many have discovered, wikipedia is often wrong and this is another case. By aligning the rotational axis parallel to the earth's axis you are actually aligning it perpendicular to the CELESTIAL EQUATOR, not the ecliptic. It is tilted at 23.5 deg. to the plane of the ecliptic as is the earth.
"...to the ecliptic, an imaginary disc containing the apparent path of the sun. Simple solar trackers are manually adjusted to compensate for the shift of the ecliptic through the seasons ..."
Another definition of ecliptic is: the plane of the earth's orbit extended infinitely (Webster's).
The ecliptic does not shift.
You have a sharp eye. The array was taken out of track mode and manually positioned for photographic purposes only.
The panels are 40 watts each.
Yes, the tracker is homebrew with some parts coming from eBay.
Yes, the gain from a tracker is dependent on latitude and time of year. Long term energy harvest is the thing to look at. Six months is adequate to see the seasonal variations since the other half of the year is a mirror.