WPFとVB.NET、TransformGroupのChildrenにAddする順番で結果が変わる

Dim tg As New TransformGroup
tg.Children.Add(New ScaleTransform(0.5, 1.2))
tg.Children.Add(New RotateTransform(30))
Dim b As New Border
b.RenderTransform = tg

Class MainWindow
    Private mihonRotateScale As Border
    Private mihonScaleRotate As Border


    ''' <summary>
    ''' TransformGroupの中から指定したTransformを返す
    ''' </summary>
    ''' <param name="tGroup">RenderTransformとか指定</param>
    ''' <param name="tType">取得したいTransformの指定、RotateTransformとか</param>
    ''' <returns></returns>
    Private Function GetTransform(tGroup As TransformGroup, tType As Type) As Transform
        For Each c As Transform In tGroup.Children
            If tType = c.GetType Then
                Return c
                Exit For
            End If
        Next
        Return Nothing
    End Function

    Private Function ResetScaleRotate() As TransformGroup
        Dim tg As New TransformGroup
        tg.Children.Add(New ScaleTransform(1, 1))
        tg.Children.Add(New RotateTransform(0))
        Return tg
    End Function

    Private Function ResetRotateScale() As TransformGroup
        Dim tg As New TransformGroup
        tg.Children.Add(New RotateTransform(0))
        tg.Children.Add(New ScaleTransform(1, 1))
        Return tg
    End Function

    Private Function GetBorder(tg As TransformGroup) As Border
        Dim b As New Border
        With b
            .Width = 100
            .Height = 100
            .Background = Brushes.Red
            .RenderTransformOrigin = New Point(0.5, 0.5)
            .RenderTransform = tg
        End With
        Return b
    End Function

    Private Sub SetBorder(b As Border, x As Double, y As Double)
        Canvas.SetLeft(b, x)
        Canvas.SetTop(b, y)
        canvas1.Children.Add(b)
    End Sub
    Private Sub ChangeAngle(b As Border)
        Dim tg As TransformGroup = b.RenderTransform
        Dim ro As RotateTransform = GetTransform(tg, GetType(RotateTransform))
        ro.Angle = 30
    End Sub

    Private Sub ChangeScale(b As Border)
        Dim tg As TransformGroup = b.RenderTransform
        Dim s As ScaleTransform = GetTransform(tg, GetType(ScaleTransform))
        s.ScaleX = 0.5
        s.ScaleY = 1.2
    End Sub

    Private Sub MainWindow_ContentRendered(sender As Object, e As EventArgs) Handles Me.ContentRendered
        Dim b As Border = GetBorder(ResetRotateScale)
        mihonRotateScale = b
        Call SetBorder(b, 30, 50)

        b = GetBorder(ResetScaleRotate)
        mihonScaleRotate = b
        Call SetBorder(b, 200, 50)
    End Sub

    Private Sub bt1_Click(sender As Object, e As RoutedEventArgs) Handles bt1.Click
        mihonRotateScale.RenderTransform = ResetRotateScale()
    End Sub

    Private Sub bt2_Click(sender As Object, e As RoutedEventArgs) Handles bt2.Click
        Call ChangeAngle(mihonRotateScale)
    End Sub

    Private Sub bt3_Click(sender As Object, e As RoutedEventArgs) Handles bt3.Click
        Call ChangeScale(mihonRotateScale)
    End Sub

    Private Sub bt4_Click(sender As Object, e As RoutedEventArgs) Handles bt4.Click
        mihonScaleRotate.RenderTransform = ResetScaleRotate()
    End Sub

    Private Sub bt5_Click(sender As Object, e As RoutedEventArgs) Handles bt5.Click
        Call ChangeAngle(mihonScaleRotate)
    End Sub

    Private Sub bt6_Click(sender As Object, e As RoutedEventArgs) Handles bt6.Click
        Call ChangeScale(mihonScaleRotate)
    End Sub

    Private Sub sld1_ValueChanged(sender As Object, e As RoutedPropertyChangedEventArgs(Of Double)) Handles sld1.ValueChanged
        Dim tg As TransformGroup = mihonRotateScale.RenderTransform
        Dim r As RotateTransform = GetTransform(tg, GetType(RotateTransform))
        r.Angle = sld1.Value

    End Sub
End Class

Wpf_test122_TransformGroupにAddする順番 - Visual Studio Team Services
https://gogowaten.visualstudio.com/WPF/_git/WPF_test7?path=%2FWpf_test122_TransformGroup%E3%81%ABAdd%E3%81%99%E3%82%8B%E9%A0%86%E7%95%AA&version=GBmaster&_a=contents