Erronous documentation for property decorators?

At https://www.typescriptlang.org/docs/handbook/decorators.html

..it reads under "Property Decorators"

If the property decorator returns a value, it will be used as the Property Descriptor for the member.

NOTE  The return value is ignored if your script target is less than ES5.

I'm running a simple example with target ES6

function MyPropDesc() {
  return function (targetProto: Object, propName: string | symbol)   {
    return {
      get: function() { console.log('in getter') }
    }
  }
}

class SomeClass {
  @MyPropDesc()
  someMember;
}

However, this doesn't seem to work. Also, when debugging this, my property decorator is being called from Reflect.js's DecoratePropertyWithoutDescriptor which ignores the result from the descriptor. And...typescript requires the decorator to return void or any. Documentation mistake?