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The solution in (2) can be given by the worst CoH2-player in the history of the game, and still be correct. You don't need to be a good player to solve a problem.
The playercard argument should not be used at all from anyone (it creates hostility, turn a balance debate into personal issue and as you say even a bad player can solve (or identify) a problem).
Since nearly all units can be countered but all units are not balanced, an argument that there is a counter to something so it does not need balance changes hold little water...
In this example countering 280 mp 30FU emplacement with 2 volks 2 shrecks 2 puppen (1040 mp 180 MU) is not much of argument either because the same proposed counter accomplice very little if it was support with lest say an HMG...