bowlesj - It's possible to see what tracks have notation in the Realtrack Picker. Please see my screenshot below - the Chart column will have something in it if there's notation of any sort.

As for "when this started", I believe there was originally no notation when Realtracks were introduced. Notation for many instruments has to be entered manually, which is a lot of work, so it's mostly older Realtracks that don't have notation.

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Realtrack Chart Notation.png (117.01 KB, 108 downloads)

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