Wales ask to play all Six Nations home games under closed Cardiff roof

• Rob Howley believes it leads to better games at the Principality Stadium • Wales host England and Ireland in Cardiff in 2017 Six NationsWales have asked Six Nations organisers to classify the Principality Stadium as a closed-roof ground, meaning all matches in the tournament would be played under cover regardless of the weather.The roof may be closed currently only if both teams agree, which has led to mind games in the week of a match. With bonus points being trialled in the Six Nations this year, the Wales interim head coach, Rob Howley, believes it is the ideal opportunity to take advanta…