-;;; NIL means nothing so far, no actual arg info has NILs
-;;; in the metatype
-;;; CLASS seen all sorts of metaclasses
-;;; (specifically, more than one of the next 4 values)
-;;; T means everything so far is the class T
-;;; STANDARD-CLASS seen only standard classes
-;;; BUILT-IN-CLASS seen only built in classes
-;;; STRUCTURE-CLASS seen only structure classes
+;;; NIL: means nothing so far, no actual arg info has NILs in the
+;;; metatype
+;;;
+;;; CLASS: seen all sorts of metaclasses (specifically, more than one
+;;; of the next 5 values) or else have seen something which doesn't
+;;; fall into a single category (SLOT-INSTANCE, FORWARD).
+;;;
+;;; T: means everything so far is the class T
+;;; STANDARD-INSTANCE: seen only standard classes
+;;; BUILT-IN-INSTANCE: seen only built in classes
+;;; STRUCTURE-INSTANCE: seen only structure classes
+;;; CONDITION-INSTANCE: seen only condition classes