Do student perceptions of instructor partisanship (internal factors) or chocolate treats (external factors) matter more to student scores of instructor effectiveness? Within the broader literature concerned with whether course evaluations are unbiased measures of instructor effectiveness, some have suggested that the provision of a chocolate treat immediately prior to distribution and completion of student course evaluations positively affects student scores of instructor effectiveness. Others have noted the negative effect of instructor partisanship on student scores of instructor effectiveness. Missing is a comparative analysis of whether external or internal factors weigh more heavily on student scores of instructor effectiveness. This study fills that lacuna through combining experimental and survey methods to simultaneously scrutinize the effect of internal and external factors on student evaluations of instructor effectiveness. Our findings indicate that perceptions of instructor partisanship significantly affect these evaluation score. We find that chocolate, on the other hand, has only a very slight positive effect on student perceptions of instructor effectiveness. This effect is not statistically significant. The upshot is one may consider pausing before sharing chocolate or partisan views in class.