irrelevant the fact he could cut it is all that matters not that he needs his shikai or bankai to cut toshiro anyway so I don't why you keep bringing this up as this is going to help hitsugaya In his matchup against kenpachi not a lot people can defeat Zaraki in a straight up fight.
all matter cease to exist it doesn't negate hax. Afterwards this happens.
irrelevant also Gerard is a big target whereas Zaraki isn't so it is avoidable plus it is easy to break out of his ice a lot of strong opponents have done so already. Hitsugaya it's not that strong physically nor is his reiatsu all that great either. It was byakuya that land the killing blow on gerard anyway not hitsugaya he has no attacks that are actually lethal towards other strong opponents.