GAA could help IRFU
It is the promotion of Ireland as a host and venue for the fourth biggest sporting event in the world.
A joint bid could work, but large parts of the country would be left out of the World Cup without major redevelopment. The IRB tends to favour one country bids now because the atmosphere can go flat in certain countries. If the IRFU went alone with the GAA you could have Wales v England in Pairc Uí Chaoimh, France v New Zealand in Salthill and Ireland playing in Casement Park.