Checking for shape intersection

I've tried somthing like:

Shape1.GetPosition x,y
Shape2.IsOnShape (x,y)

but it's too slow. Now I'm using:

Set tempShape=shape1.Intersect(shape2)
tempShape.Delete

which looks clumsy but (Surprisingly!)is not slower then the first and is much more reliable.Can you give me any tips for improving performance?And is there any real documentation about CorelDraw12 object model ?
Thank you.