I believe no one actually did. Those who tried did fall asleep watching them
If you were right, you should see in their results that they get relatively good results against top clubs (where they can be the underdog) and not so great results against clubs of similar size. While dominant clubs usually get the expected wins and struggle as soon as they can't get their dominant play through (of course there are exceptions for both rules, as otherwise the underdogs would never win).
So let's have a look at their results this season:
They lost in Leverkusen (current double winner) and in Dortmund (CL finalist). They drew at home against Bayern and Pilsen and away at Union Berlin. They've won everything else. That's results for a top team, that only really struggles against even bigger teams but consistently wins against lesser teams or at worst might get a draw away (Union). The only exception to that would be the Pilsen result.
So I think their results actually back up my perception: They are a great counter attacking team, yes, but they do have the ability to dominate if necessary. When they take the lead and can pick off teams on the counter it's definitely what they can do best and prefer, but they know how to get that lead first as well.
Absolutely, those two have great chemistry together and really profit from each other.