Any heuristic explanation on why sieve methods can not prove strong Goldbach conjecture ?
I remember that Terence Tao published a blog and gave an heuristic explanation on why circle methods very likely will NOT be able to prove strong Goldbach conjecture (http://terrytao.wordpress.com/2012/05/20/heuristic-limitations-of-the-circle-method/#more-5963)
Is there any similar heuristic explanation on why sieve methods can NOT prove strong Goldbach conjecture ?
A related question, Is there any similar heuristic explanation on why Schnirelmann density methods can NOT prove strong Goldbach conjecture ?