is DISPID_VALUE reliable for invokes on IDispatchs from scripts?

Question

Continuing from this question, i am confused whether DISPID_VALUE on IDispatch::Invoke() for script functions and properties (JavaScript in my case

Answer 1

The default method or property that DISPID_VALUE invokes should be consistent for a given interface. That method/property has to be specified as DISPID_VALUE in the definition of the interface in the IDL for the type library. The only way it could change is if the owner of the interface released a new version of the interface that changed which method/property was the default but that would violate a fundamental rule of COM interfaces.