Currently (in RiverWare 7.0), Series Note ornaments do not show up in SCT Aggregation Summary cells.
Phil, 3-17-2017

This four-frame animation (GIF) shows the effect of both opening and closing a time aggregation, AND showing and hiding the series notes column:

This is true also in the other axis orientation:

We could either choose to unconditionally show the Notes ornament in Summary cells -- OR make this an option (checkbox) -- possibly on the SCT Config Summary Tab:

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