'LEADING SLAT ASYMMETRY AND LEADING EDGE' CAUTION LIGHT CAME ON IN CRUISE. NO APPARENT CTL PROB SO CONSIDERED A FAULTY INDICATION. PRECAUTIONS FOLLOWED FOR LNDG.

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AT CRUISE FL350 WITH NO SPD OR CONFIGN CHANGES; OBSERVED 'LEADING EDGE ASYMMETRY' EICAS MESSAGE AND 'LEADING EDGE' CAUTION LIGHT. NO SECONDARY INDICATIONS WERE OBSERVED. THIS INCLUDED A VISUAL INSPECTION; AND TAKING THE PHYSICAL CTL OF THE ACFT WITH THE AUTOPLT OFF. THE EMER PROC IS WRITTEN FOR A CONFIGN CHANGE SIT. THERE IS A CAUTION TO MAINTAIN 240 KIAS OR LESS IN THE PROC DUE TO LEADING EDGE LIMITATIONS. I LEANED TOWARDS MAINTAINING THIS SPD OR LESS; AS WE DIDN'T KNOW THE FULL EXTENT OF THE PROB AND THE OPERATING MANUAL IS NOT VERY DESCRIPTIVE OF MECHANICAL PROTECTION DEVICES; DESIGN; ETC. THE CAPT FELT THAT IT WAS AN INDICATION PROB; AND BELIEVED THAT THERE WAS LITTLE DANGER OF AGGRAVATING THE SIT. UPON ARR AT ORD WE ADVISED APCH OF HIGHER APCH SPDS; AND THE NEED FOR AN EXTENDED FINAL. WHEN CONFIGURING FOR LNDG AND ELECTRICALLY EXTENDING TRAILING EDGE FLAPS; RECEIVED A 'LEADING EDGE SLAT DISAGREE' LIGHT. THIS IS NORMAL FOR THE ASYMMETRY SIT; BUT IT IS NOT NOTED IN THE PROC. WHILE WE HAD REVIEWED THE OPERATING MANUAL; AND SYS KNOWLEDGE SHOULD'VE PRECLUDED ANY CONFUSION HERE; IT WAS DEFINITELY A DISTR TO REVIEW ANOTHER EXTENSIVE EMER PROC; TO ENSURE THAT NOTHING IN IT APPLIED. AT THE COMPLETION OF THE FLT; THE CAPT WAS UNAWARE OF THE REQUIREMENT TO PULL THE COCKPIT VOICE RECORDER CIRCUIT BREAKER WHEN THERE IS A FLT CTL PROB. IN SPITE OF POINTING THIS OUT TO HIM; HE ELECTED NOT TO COMPLY; AS HE COULD NOT FIND THE REF. RECOMMENDATION: NOTE IN THE 'LEADING EDGE FLAP ASYMMETRY' PROC POINTING OUT THAT THE 'LEADING EDGE SLAT DISAGREE' LIGHT WILL NORMALLY COME ON; AND HAS NO EFFECT ON PROC OR CONFIGN REQUIREMENTS. MORE NARRATIVE REGARDING LEADING EDGE MECHANICALS AND IF THERE IS MUCH OF A THREAT IN CRUISE OF THEM EXTENDING UNCOMMANDED.