Yes, that's right. There were two readings, left and right of track, we would report the highest and write it on the flight progress strip. It use to get added to the Daily Movement Register. I can't remember why it was stopped but I am glad it was so we could back to proper ATC.
For a time I was in charge of the chap who looked after the Noise and Track Monitoring but I have to say I didn't take a great deal of interest! :-)