Op-Amp dynamic hysteresis
Dynamic hysteresis is hysteresis that does not persist. You might have a capacitor only or a capacitor + resistor in the positive feedback so that the hysteresis is large initially then peters out over time.
This has the effect of the comparator ignoring small changes in the input that occur immediately after the comparator changes state.
Ordinary hysteresis is persistent- once the comparator switches, the threshold changes to the new threshold for all time.
In the case of the app note section, they apply a capacitor as a fudge to compensate for oscillation due to parasitic coupling.