This script can help to improve a difficult track by averaging the results of two or more trackers.
Note: This script requires After Effects 6.5 or later.
Select any number of trackers (i.e. select Tracker 1 and Tracker 2) then run this script.
It calculates the average of those trackers, creating a new 'averaged' track. You can then use the Tracker Controls palette to select and apply the new track.
The script works with either 1, 2 or 4 point tracks and it's possible to select trackers from multiple layers.