by Paul Cook - The weight of history may well be the biggest obstacle facing Wales as they embark on the defence of their Six Nations title this weekend. Back-to-back winners in 2012 and 2013, the Welsh are striving to become the first country ever to secure a hat-trick of outright titles in a row since the Championships began back in 1883. France had their name on the trophy four times in succession between 1986 and 1989 but two of those titles were shared and it is indeed the French that recent history dictates should be the side Wales have to beat this time around in order to etch their names into the annals of the game. The last four post-Lions tournaments have been won by Les Bleus, two by way of a Grand Slam, in a fair indication of the toll a Lions tour inevitabl