In 1991, McBride, Rivers, Kopf, et al., in an essay about clinical features of dysplastic nevi, made this riveting statement [8]: "One way to define the atypical moles in this [dysplastic nevus] syndrome is to use the same acronym—ABCD—that we first described to diagnose MM [malignant melanoma]. The same attributes—Asymmetry, Border Irregularity, Color Irregularity, and Diameter of 6mm or more—also correlate with the clinical characteristics of the atypical moles seen in patients with 'classic' dysplastic nevi." In Resolving Quandaries, Ackerman responded to the proposition of McBride, Rivers, and Kopf, et al., to the effect that the ABCDs were as effective for diagnosing dysplastic nevi clinically as they were for melanomas in these words: "Such a suggestion is startling—the very same criteria used for identification of melanoma recommended for recognition of melanocytic nevus, and moreover, the most common one, i.e. Clark's nevus. How can the same criteria be employed for diagnosis of a nevus and a melanoma, two melanocytic neoplasms that are diametric, clinically, histopathologically, and biologically? They cannot and should not!" [4]

In 1995, Ackerman asserted that the ABCDs were "flawed seriously," undertaking then a critique of what he deemed to be the serious limitations of border irregularity and the number 6 mm for diameter. He said that "to assess irregularity of a border, an agreed-upon measuring stick for judging border regularity must be established, but none has been proferred by proponents of the alphabetical guide to diagnosis of melanoma." About diameter he stated that "Many melanomas are identifiable when they are as small as 3-4 mm in greatest dimension." [4]

In 1998, Sagabiel wrote of clinical characteristics that can aid in the recognition of early melanoma as follows: "These have been summarized by the American Cancer Society as the ABCDs of melanoma . . . An 'E' might be added to these ABCDs for a changing or asymptomatic elevation." [9] This is how Ackerman commented on the suggestion of Sagebiel: "'E' for Elevated is not a sign of early melanoma; F for Flat is." [10] Sagebiel also supported the concept of Friedman, Rigel and Kopf that "dysplastic nevi" often have some characteristics positive for the ABCDs, [9] a notion that Ackerman rejected as being "illogical" and "devoid of legitimacy." [10]