It gradually became more difficult over the 1980s, the 1970s and the 1990s are two different worlds in the NHL. When Clarke won back-to-back Harts, the league had three Swedes as its international contingent while some prominent Canadians like Bobby Hull were in the WHA.So the best players from the late '70s should not have had any success in the '80s if their stats were inflated by the weaker competition in the 70s right?