One will not be able to trace the patterns by looking at ones eye movements.  One can only tell the general direction they are staring not what they are seeing w/in those confines. 

Even sub-break through patterns with open eyes tend to be rapidly changing. W sub-break through many times the more intense visuals are with eyes closed.  Another thing I have noticed is that it is very difficult to actually "see" the detail of the patterns on lower doses.  It is as if it is an illusion.  They are there but can not be analyzed.  It is similar to how the blind spot will fill in information but when one tries to analyze the details they can not.  Try it next time, on higher doses it becomes a little more clear but there is still a rapidly evolving illusionary nature to the visuals. 

It is a good idea but the results are likely to not be very satisfying.  Not only the inherent difficulty in the identification of the patterns themselves and there rapid motion, morphing, changing identity.  Additionally people have great difficulty even drawing or explaining the patterns.  Even artists have trouble although Alex Grey is pretty good.  It will be just as hard to trace them as they have a illusive nature as well as their other properties.  It just does not seem like it will be effective in practice.  Although more characterization of these visuals is needed. 

There are studies looking at EEG while people are on hallucinogens.  Specific neural regions have been correlated with specific types of categories of the psychedelic experience.  See Vollenweider's work.  Also a group out of germany has put out several articles in the last year on similar studies.