Wales coach Shaun Edwards argues that winning a Six Nations Grand Slam is more difficult than reaching the Rugby World Cup Final in The Guardian.
"Champions of Europe or champions of the world; which is harder? No difficulty with that one, but when you ask whether it's more difficult to get to a World Cup final or to win a grand slam in the Six Nations, then I'd argue it's less obvious. In fact, if the World Cup seedings help you into one of the less demanding groups at the global gathering – and this I have to admit is on the evidence of being at just the one World Cup – I'm pretty certain the slam takes the prize.
"Why? Well, 2011 in New Zealand suggested that it is possible to get to the World Cup final after just two or three difficult games whereas, depending on how the fixtures fall, the slam can be a shocker because no game is a walkover and three of the five could be away from home, rather than on (supposedly) neutral territory."