From: Patent Tactics, George Brock-Nannestad ----- this is what we all do. However, Richard took the signals from the "edge" tracks (i.e. those almost ½ inch apart), realizing that the 1 kHz signals (a _low_ frequency) were in phase in all channels, and generated the Lissajous from these. This is a good (and novel) way to obtain precision. The need for obtaining a maximum amplitude reading does not arise at this low frequency - you cannot tilt the head so much that you get an erroneous "lower" maximum at this frequency, unless it is a monitoring tape at very, very low speed.
Thank you, Richard, for this neat trick!