As far as i know, 8 blobs indicate the "extent" of the selection. Xara not only uses these blobs to show a selection. Please also be aware of the single points to the top left corners of any selected object.
Maybe this topic will lead to an "intermediate selection" or modification scheme?
Xara can put the same toggle "distinct" button next to Show selection bounds - Show object edit handles - Show fill edit handles and Show rotation handles for this scenario to take effect without delving into blobs etc.
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