Well, in the base language you couldn't store function pointers in variables or record fields, since they might refer to nested subroutines that included a context pointer to their parent subroutine stack frame, and invoking them after it had returned would be catastrophic. This “downward funargs restriction” made OO-style programming in standard Pascal very difficult in a way that it isn't in standard C. So I think the OO features, too, aimed at a weakness of the base language—but I admit I never looked at Apple's version.