It's relevant when considering that Stormont is currently in crisis due to arrests relating to possible IRA murders. It's going to be brought up a lot so we should probably get used to it. Speaking of McDonnell, I couldn't see him on the front bench anywhere? Wonder if they kept him away so there wasn't that distraction.
As to PMQs, there were two sides - first, Corbyn's demeanour itself was very good, and asking questions from the public does largely prevent Cameron bringing out Flashman. In that sense, it's a very good defensive tactic that got him through the session without getting attacked himself. Cameron actually answers the questions and it's generally quite a pleasant affair. However that brings us on to the second point, which is that it's Cameron that's supposed to be under pressure from attack, not Corbyn. He found it staggeringly easy today. He could just trot out stuff on the improving economy, mention that Labour will spend unlimited amounts on benefits and give away our nukes. The questions were all worthy of being asked, but they didn't pin him down on any area that the government might find awkward or embarrassing, or that he didn't know the answer to.