Postsharp 2. Readable code?

[Serializable]
[IntroduceInterface(typeof(INotifyPropertyChanged), OverrideAction = InterfaceOverrideAction.Ignore)]
[MulticastAttributeUsage( MulticastTargets.Class, Inheritance = MulticastInheritance.Strict )]
public sealed class NotifyPropertyChangedAttribute : InstanceLevelAspect, INotifyPropertyChanged
{
    [ImportMember( "OnPropertyChanged", IsRequired = false )]
    public Action<string> BaseOnPropertyChanged;

    [IntroduceMember( Visibility = Visibility.Family, IsVirtual = true, OverrideAction = MemberOverrideAction.Ignore )]
    public void OnPropertyChanged( string propertyName )
    {
        if ( this.PropertyChanged != null )
        {
            this.PropertyChanged( this.Instance,
               new PropertyChangedEventArgs( propertyName ) );
        }
    }

    [IntroduceMember( OverrideAction = MemberOverrideAction.Ignore )]
    public event PropertyChangedEventHandler PropertyChanged;

    [OnLocationSetHandler, MulticastSelector( Targets = MulticastTargets.Property )]
    public void OnPropertySet( LocationInterceptionArgs args )
    {
        if ( args.Value == args.GetCurrentValue() ) return;

        if ( this.BaseOnPropertyChanged != null )
        {
            this.BaseOnPropertyChanged( args.Location.PropertyInfo.Name );
        }
        else
        {
            this.OnPropertyChanged( args.Location.PropertyInfo.Name );
        }
    }
}