This is the most baffling argument I've ever heard!
Right - I'll say this slowly and clearly - what bearing does someone's place of birth have on their ability as a footballer? (Hint: The answer is none).
The fact he is from Germany - a country with many, many, many good footballers - does not...
But using the word "international" is a nonsense when comparing the qualities of players though, isn't it? It's complete luck which country they are born in, nothing to do with ability. Baffling argument.
Alright, just to prove it's a bollocks argument;
Manchester United
Valencia - Ecuador...
It's entirely relevant because it's Gross' ability that's being discussed. Saying "he's nowhere near his national squad" is an entirely unfair way to judge him as a player, as he had no choice as to his birth nationality. It's a completely nonsense and meaningless argument.
Example - Ahmed...
Also, not a fair way to judge him. Germany have insane depth. If he was from about 28 of the other 31 countries, he'd be at the tournament. If he was at a team of the ability of Sweden downwards, he'd probably be their best player.