NCP1340B4 QR Flyback qu's

[Faringdon]

Hi,
***Can you use just one Brownout diode with NCP1340B4 ?...
NCP1340B4 has 2 diodes connected (OR'd) from the AC points of the bridge, to the HV pin...which then does...
1...startup
2...brownout detection
3...Recovery from brownout
4...X2 cap discharge.

We dont care about X2 cap discharge...But want brownout and "Recovery from brownout", and HV startup.

So can we use just one diode here?
the datasheet doesnt make it clear.....it  implys that one diode would be ok for brownout detection...but does not make it clear that recovery from brownout, or startup,  would be possible with just one diode?

***Why does V(ZCD pin) need to be at least 8V when the secondary is conducting?, ..as said by page 15 of the NCP1340B4 datasheet
Even with high leakage current, there is no chance that even if V(ZCD pin) was only 5V, that the ZCD pin would ring below 80mV (The ZCD comparator threshold).
So why minimum of 8V?

NCP1340B4
https://www.onsemi.com/products/power-management/acdc-power-conversion/offline-controllers/ncp1340