It seems on the RealTracks dialog, out of range values are just blocked at -100 or 100
On RealDrums, a pop-up tells you the value is out of range.
On the song form it appears, knowingly or otherwise, to do some kind of calculation and uses whatever is left after the calculation.

The sanity-checking on the RealTracks and RealDrums dialogs is OK.
That on the Song Settings page is crass.
Sigh!

Jazz relative beginner, starting at a much older age than was helpful.
AVL:MXE Linux; Windows 11
BIAB2025 Audiophile, a bunch of other software.
Kawai MP6, Ui24R, Focusrite Saffire Pro40 and Scarletts
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