But along with multiple Grand Slam-winning ex-France back-row Serge Betsen, the 2005 Six Nations player of the tournament gave us an insight into life in an elite back-row and stories from their careers.
And Williams touched on the something fueled by a Warren Gatland comment in 2009 that in recent years Wales see Ireland as their biggest antagonist rather than England.
Well, to be more precise, the Wales head coach, said at the time: "Recent Welsh experiences against Ireland, at international and provincial level, have not always been the greatest. Of all the teams in the Six Nations, the Welsh players dislike the Irish the most and they are all very motivated to be playing on Saturday."
"I think the first Grand Slam, [Gatland] was quite quiet and then he came up with some absolute pearlers," said Williams by way of prelude nine years on tonight.
"Obviously the famous one that the Welsh boys hate the Irish more than the English, that's impossible. So I don't know where he got that from. I think that was more of a personal kind of dig. But he does throw some bombshells."
"He just instilled an unbelievable belief in us. He bluffed us into thinking we were fitter, faster and stronger than every other side" - Martyn Williams on the Warren Gatland effect #OTBHRC @Heineken_IE pic.twitter.com/g9ZDCINUzz
— Off The Ball (@offtheball) February 23, 2018
Williams added: "I love the Irish!"
But he does feel a healthy rivalry has built up over recent years fueled by high reward games.
"I think between 2005 and 2015, between us we won seven tournaments. So basically we were much better than England at that time, weren't we," he said to cheers from the Mansion House audience.
"Our first Grand Slam in '05 was against Ireland. '08 was a Triple Crown game. '09, the Wales-Ireland game was for the Grand Slam, so it always seemed to be these huge games. The World Cup in 2011 as well."
The full chat will be available as a podcast and on our social channels.