Exhaust temp sensors

[FreshMar at aol.com]

 Has anyone tried thermosensors on individual exhaust pipes, to monitor 
the exhaust temps for more analytical data? They could return the optimum 
exhaust temp (600F?),any higher could be interpreted as 'too lean'. This 
could be another cheap engine tuning tool? Or wont it? It will not be 
immediate or instantanious, but could show differences in each cylender, 
providing the thermosensors are of high quality and equally accurate.
Mario T.