KnifeItem attack cooldown (v50)

/**
 * Although the KnifeItem.prefab says `useCooldown: 0`, the `KnifeItem.HitKnife` has a special logic:
 * (Unrelated parts omitted)
 */
public class KnifeItem : GrabbableObject
{
    public int knifeHitForce = 1;

    public override void ItemActivate(bool used, bool buttonDown = true)
    {
        if (base.IsOwner) { HitKnife(); }
    }

    public void HitKnife(bool cancel = false)
    {
        if (!cancel)
        {
            objectsHitByKnife = Physics.SphereCastAll( /* ... */ );
            objectsHitByKnifeList = objectsHitByKnife /* ... */ ;
            for (int i = 0; i < objectsHitByKnifeList.Count; i++)
            {
                if (/* hit on special layers */) { /* ... */ }
                else
                {
                    if ( /* hit on walls, floors, etc., */ ) continue;
                    try
                    {
                        if (Time.realtimeSinceStartup - timeAtLastDamageDealt > 0.43f)  // <-- [!]
                        {
                            timeAtLastDamageDealt = Time.realtimeSinceStartup;
                            component.Hit(knifeHitForce, forward, previousPlayerHeldBy, playHitSFX: true, 5);
                            bloodParticle.Play(withChildren: true);
                        }
                    }
                    catch (Exception arg) Debug.Log("...");
                }
            }
        }
    }

    // other methods ...
}