How to Stretch WPF Tab Item Headers to Parent Control Width

Question

Is there a way in XAML to cause the tab item headers to stretch across the width of the tab control?

For example, I have three tabs: red, blue and green. If I have a

Answer 1

I am an old school style guy. and prefer this kind of functionality to encapsulate into the code of the control itself. My derived control looks like following:

    public class CustomTabControl :TabControl
{
    protected override void OnRenderSizeChanged(System.Windows.SizeChangedInfo sizeInfo)
    {
        foreach (TabItem item in this.Items)
        {
            double newW = (this.ActualWidth / Items.Count) - 1;
            if (newW < 0) newW = 0;

            item.Width = newW;
        }            
    }       
}

and my XAML looks like

Can someone explain why everyone prefers styling control instead of deriving.