SCD comment: rule for predicate of simpleType

The description of the predicate in steps for simple types
says that the predicate is:

     If {variety} is union and the [name] is empty, the pair
     {position, n} where n is the position of the simple type
      definition among {member type definitions}

but I think the text needs to distinguish between the {variety}
of the simple type being selected in the step and that of its
parent, if any.

A top-level simple type which happens to be a union does not
need a numeric predicate; its name will sufficiently identify
it.  It is only an anonymous simple type defined within a
union that needs a number.

Or am I wrong?

-CMSMcQ