"Base class for messages with `simple' method combinations.
A simple method combination is one which has only one method role other
- than the `before', `after' and `around' methods provided by BASIC-MESSAGE.
- We call these `primary' methods, and the programmer designates them by not
- specifying an explicit role.
+ than the `before', `after' and `around' methods provided by
+ `basic-message'. We call these `primary' methods, and the programmer
+ designates them by not specifying an explicit role.
If the programmer doesn't define any primary methods then the effective
method is null -- i.e., the method entry pointer shows up as a null