You guys are all reading too much into it.
The head honcho has 2 goals in this duel:
1- Confirming the unique skill "Dual Wield" existence and it's potential, if none of you noticed it, when Kirito used it, his HP didn't drop just from boss attacks, If i'm seeing it right, the use of the skill is quite risky.
2- Ensuring Asuna's security, Asuna is a formidable player for a team, but she NEVER soloed and since she joined the guild all her skills were balanced which gave her the opportunity to develop combat-useless skills like cooking and such, notice that Kirito has absolutely NO crafting skills, he only focused on developing combat skills which paid him well since he solo plays. GM wants to make sure Kirito can properly defend their ACE and to show everyone that not even a Guild Master, who is likely very well skill-developed, couldn't endanger Kirito. This would mean that no one would be stupid to attack Kirito.
Of course this does not count the rogue assassins guild as they already have Kirito in their sights.
This duel is more a showoff to make Asuna safe from normal assholes that would want to provoke something, like someone wanting to carelessly duel Kirito to prove he is a cheater or something, thing is I think I know why he has that skill and it has to do with him constantly using 1hander without a shield. Kirito's stats were growing in offensive way, while if he was using a shield his stats would grow more defensively. That allowed him to learn the Dual Wield.
