Return "this" as rvalue

The following code does, as expected, not compile

#include <iostream>

class A
{

  public:

    A() = default;
    ~A() = default;

    A(const A&) = delete;
    A(A&&) = delete;

    A& operator=(const A&) = delete;
    A& operator=(A&&) = delete;

    A& operator<<(const int i)
    {
      std::cout << "operator<< called" << std::endl;
      return *this;
    }

};

void foo(A&& a)
{
  std::cout << "foo called" << std::endl;
}

int main()
{
  A a; a << 14;
  foo(std::move(a)); // works fine

  foo(A() << 14);    // does not compile

  return 0;
}

Changing the class A to

class A
{

  public:

    A() = default;
    ~A() = default;

    A(const A&) = delete;
    A(A&&) = delete;

    A& operator=(const A&) = delete;
    A& operator=(A&&) = delete;

    A& operator<<(const int i) &
    {
      std::cout << "operator<< called on lvalue" << std::endl;
      return *this;
    }

    A&& operator<<(const int i) &&
    {
      std::cout << "operator<< called on rvalue" << std::endl;
      return std::move(*this);
    }


};

makes the program compile. However, return rvalues with std::move is usually not a good idea, since it will return dangling references or prevents the compiler to do certain optimizations.

Is the described case one of the few exception from the rule of thumb "do not return by rvalue" or should the issue be resolved differently?

Great thanks!