The cat is out of the bag. Now we know why the players from China are going for the early Bf5. Drummroll please for the variation that curtains the mainline of the Petroff:
The biggest advantage of the Petroff is that it not only dodges the discussion in the Berlin, it can also dodge the Italian, the Scotch and the Four-Knights, although black has to go slightly offbeat to do so.
Play it safe!