How apply "Reduce Nodes" in VBA?


I have an outline shape selected. To reduce the number of nodes, I do it manually as:

1. Click Shape Tool

2. Click "Select all nodes" button on the toolbar

3, Click Reduce nodes button on the toolbar

That works fine but how do I achieve this in VBA?

I tried this:

shp.Curve.Nodes.All.AutoReduce (0.5)

But the results don't match with the result of manual work. Further, the manual work did not require any "Precision Margin" value like 0.5 here.