@Operatix I don't think so. It's only ideal because he is a main character in this manga. Like he has stated: they have 2 special skills that they know nothing of , using it on the life death situation is worst thing they can do, it can lead to the destruction of the team (for example: berserker skill: use 99% user's HP and stamina to deal a massive damage to enemy, and the boss like: "YOU FOOL!! THIS ISN'T EVEN MY FINAL FORM" ).
Considering the skill's effect, I think Arihito could have run to one of his party member's back to block the attack. Or at least, take the cover somewhere like the pillars along the stair.