Can a Magus Kensai Use Perfect Strike Multiple Times on a Crit?

The Perfect Strike ability states:

At 4th level, when a kensai hits with his chosen weapon, he can spend 1 point from his arcane pool in order to maximize his weapon damage. Don’t roll for damage—the weapon deals maximum damage. This affects only the weapon’s base damage dice, not additional damage from sneak attack, magical weapon properties, spellstrike, or critical hits. If the kensai confirms a critical hit, he can instead spend 2 points from his arcane pool to increase his weapon’s critical multiplier by 1.

However there is nothing on the table of bonuses that effect crit multipliers or even says that it is a bonus in the first place. Can the Kensai use perfect strike multiple times to continuously increase the crit multiplier?