Poor performance (stuttering) with Windows Phone 7 Page Transitions

Question

I tried using Toolkit for page transitions, but all animations stuttered. In another question, I was asked not to use the toolkit, so I myself implemented all the animations and manually started them. For example, going to another page:

void list_SelectionChanged(object sender, SelectionChangedEventArgs e)
{
    ListBox listBox = sender as ListBox;
    if (null == listBox) return;
    Data.Category item = listBox.SelectedItem as Data.Category;
    if (null == item) return;

    Uri uri = new Uri(App.MakeResourcePathTo(item.Page), UriKind.Relative);

    Storyboard storyboard = Application.Current.Resources["FlipForwardOut"] as Storyboard;
    Storyboard.SetTarget(storyboard, LayoutRoot);
    EventHandler completedHandler = delegate { };
    completedHandler = delegate
            {
                NavigationService.Navigate(uri);

                storyboard.Stop();
                storyboard.Completed -= completedHandler;
            };
    storyboard.Completed += completedHandler;
    storyboard.Begin();

    listBox.SelectedIndex = -1;
}

Is the code good? There, as I understand it, there will be nothing else that runs parallel to this code. This is exactly what I wanted, because then nothing would hinder my animation and slow it down.

Here is another piece of code. This shows how I handle inverse animation.

protected override void OnBackKeyPress(System.ComponentModel.CancelEventArgs e)
{
    e.Cancel = true;
    Storyboard storyboard = Application.Current.Resources["FlipBackwardOut"] as Storyboard;
    Storyboard.SetTarget(storyboard, LayoutRoot);
    EventHandler completedHandler = delegate { };
    completedHandler = delegate
    {
        storyboard.Stop();
        storyboard.Completed -= completedHandler;

        NavigationService.GoBack();
    };
    storyboard.Completed += completedHandler;
    storyboard.Begin();
}

Is there something wrong with this code that might cause performance issues?

Animations are very simple, only linear animations:

<Storyboard x:Key="FlipForwardOut">
    <DoubleAnimationUsingKeyFrames Storyboard.TargetProperty="(UIElement.Projection).(PlaneProjection.RotationY)">
        <LinearDoubleKeyFrame KeyTime="0" Value="0"/>
        <LinearDoubleKeyFrame KeyTime="0:0:0.4" Value="70"/>
    </DoubleAnimationUsingKeyFrames>
    <DoubleAnimationUsingKeyFrames Storyboard.TargetProperty="(UIElement.Opacity)">
        <LinearDoubleKeyFrame KeyTime="0" Value="1"/>
        <LinearDoubleKeyFrame KeyTime="0:0:0.4" Value="0.1"/>
    </DoubleAnimationUsingKeyFrames>
</Storyboard>

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Answer 1

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