Why do you think that is not the case? Intellisense would tell you there is no Width property. Recording a macro will give the syntax if needed. There is a difference between chart and plot area.

ActiveChart.ChartArea.Select
    ActiveSheet.Shapes("Chart 1").ScaleWidth 1.0760456274, msoFalse, _
        msoScaleFromTopLeft
    ActiveSheet.Shapes("Chart 1").ScaleHeight 1.1590214067, msoFalse, _
        msoScaleFromTopLeft
    ActiveChart.PlotArea.Select
    Selection.Width = 356.428
    Selection.Height = 227.532
Try selecting the chart manually and then in the Immediate Window of the VBE, type: ActiveChart.
The period would open the intellisense options.