[Avodah] Kiddush Levana on Motzai Tisha B’av

[Micha Berger via Avodah]

On Tue, Sep 26, 2017 at 07:34:30AM +0200, Ben Waxman via Avodah wrote:
: If the reason is z'rizin is the reason, than why not do it on the
: 4th of Av? Why let the aveilut override the tefila? ...

I am confused. Isn't the implication simply that all else being equal,
do it earlier because zerizin, but aveilus is sufficient for not
considering all else equal?

Why does zerizus being applicable mean that it is necessarily the most
urgent halachic principle coming into play?

GCT!
-Micha