If you evaluation are not making sense, or you see a need to changes after starting evaluation you may consider slight changes to your evaluation system.
Hence, the short answer is YES. The longer answer is any changes to your evaluation system / point table / factor rationale will impact existing evaluations.
If you make any changes to the rationale, levels or sub-factors you should re-evaluate your Job Classes and any changes may invalidate any Pay Equity results previously obtained. If you feel your results do not properly reflect the value of a job in your organization, but you do not see any opportunity to make changes to the sub-factor evaluation you may raise or lower the weightings of sub-factors to put greater emphasis on factors more highly valued to your organization. Note, if you are using custom point totals, these will have to be updated manually.