The specs of the JVM TI RedefineClasses/RetransformClasses, Instrumentation redefineClasses/retransformClasses, JDI redefineClasses and JDWP command RedefineClasses have clarifications about unsupported changes in class redefinition and retransformation. For instance, all specs list the class file attributes that are not allowed to change. This creates some unnecessary extra work and CSR's when new class file attributes are introduced.
The suggestion is to keep this in the JVM TI spec only. Other specs (Instrumentation, JDI and JDWP) should reference the JVM TI spec description.