WPF Problem z sygnalizowaniem zmiany DepedencyProperty

Mam kilka dependency propertisów w kontrolce a zmiany są sygnalizowane tylko dla jednego (PathData)

public partial class PathControl : UserControl, INotifyPropertyChanged
    {
        /////////////////////////////////////////////////////////////////////////////////
        public static readonly DependencyProperty ViewboxWidthProperty =
             DependencyProperty.Register("ViewboxWidth", typeof(double),
             typeof(PathControl), new PropertyMetadata((double)48, SOnPropertyChanged));

        public double ViewboxWidth
        {
            get { return (double)GetValue(ViewboxWidthProperty); }
            set { SetValue(ViewboxWidthProperty, value); }
        }
        public static readonly DependencyProperty ViewboxHeightProperty =
             DependencyProperty.Register("ViewboxHeight", typeof(double),
             typeof(PathControl), new PropertyMetadata((double)48, SOnPropertyChanged));

        public double ViewboxHeight
        {
            get { return (double)GetValue(ViewboxHeightProperty); }
            set { SetValue(ViewboxHeightProperty, value);  }
        }
        /////////////////////////////////////////////////////////////////////////////////
        public static readonly DependencyProperty PathDataProperty =
             DependencyProperty.Register("PathData", typeof(string),
             typeof(PathControl), new PropertyMetadata("", SOnPropertyChanged));

        public string PathData
        {
            get { return (string)GetValue(PathDataProperty); }
            set { SetValue(PathDataProperty, value); }
        }

        private static void SOnPropertyChanged(
        DependencyObject sender, DependencyPropertyChangedEventArgs e)
        {
            var control = sender as PathControl;

            var property = e.Property;

            switch (property.Name)
            {
                case "PathData":
                    var converter = TypeDescriptor.GetConverter(typeof(Geometry));
                    control.path.Data = (Geometry)converter.ConvertFrom(e.NewValue);
                    
                    break;
            }

        }
    }

Użycie:

    <Grid>
        <TextBlock ... />
        <controls:PathControl Width="80" Height="80" 
                                   ViewboxWidth="48" 
                                   ViewboxHeight="48"
                                   PathStyle="White"
                                   Margin="107,193,113,27"                                PathData="M3.15,5.27L8.13,10.26L2.15,14V16L10.15,13.5V19L8.15,20.5V22L11.65,21L15.15,22V20.5L13.15,19V15.27L18.87,21L20.15,19.73L4.42,4M13.15,9V3.5A1.5,1.5 0 0,0 11.65,2A1.5,1.5 0 0,0 10.15,3.5V7.18L17.97,15L21.15,16V14L13.15,9Z"
                                   />
    </Grid>

Dzieje się tak ponieważ wartości które przypisujesz w xamlu do ViewboxWidth i ViewboxHeight są takie same jak wartości domyśle podane w definicji dependecy property, czyli z perspektywy wpf do zmiany wartości nie doszło :)