Perhaps because of this:Originally Posted by mac_bolan00
Usage Note: In the 15th century, the word controller developed the alternate spelling comptroller as a result of an association between the first part of the word, cont, and the etymologically unrelated word count and its variant compt. Although the historical pronunciation of comptroller would be the same as for controller, evidence suggests that the spelling pronunciations (kmp-trlr) and (kmptrlr) may now be used by a majority of speakers. In a recent survey, 43 percent of the Usage Panel indicated that they pronounce comptroller like controller, while 57 percent pronounce it with mp, as it is spelled, with stress on either the first or second syllable. And half of those Panelists who pronounce comptroller like controller indicated that they also consider the spelling pronunciations acceptable.
Source: The American Heritage® Dictionary of the English Language, Fourth Edition
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