I don't think that test does much. The original point was that there's no such thing as objective news, but rather facts put into context.
If you're finding that context setting is consistent in its narrative, that's not a reason to recoil.
As an example, put yourself in a highly contentious context of a historical situation - say the apartheid in South Africa. If you found a newspaper that always took a position counter to the white south African government, you would have found a good newspaper.
That doesn't always work, but neither does a simple test like you've deviced.
If you're finding that context setting is consistent in its narrative, that's not a reason to recoil.
As an example, put yourself in a highly contentious context of a historical situation - say the apartheid in South Africa. If you found a newspaper that always took a position counter to the white south African government, you would have found a good newspaper.
That doesn't always work, but neither does a simple test like you've deviced.