Possible Clues:

• Intellectual contest (3 words)
• Fighting talk
• How does one decide who is the best comedian as Behan and Beckett make a contest of it?
• Ablest two fit to engage in intellectual competition
• *Chess match, e.g. (see letters 5 to 7)
• How does one decide who is the best comedian as Behan and Beckett make a contest of it
• Contest in which intelligence rather than violence is used
• Presumably the loser here will die laughing, as it's a funny way of fighting
• Wilde has words with Behan in Siege of Limericks?
• The result of engaging comedians?