His Royal Highness –
To say that a city is defined by the size of the Digali Hamidbar should have been mentioned by the Rishonim. If the Rishonim could ask where does Rashi learn that shishim ribo is a criterion of a reshus harabbim, how much more so can we ask on Rav Moshe where does he learn that this is the classification of a city.
I gave a citation. More people go out of Brooklyn to work than come into Brooklyn.
I give you the job of finding out. I have tried; he is really not interested in talking about the inyan. I believe that he maintains that since his father objected no one can come and say otherwise.
As I mentioned he should have adjusted for the Boro Park teshuvah in 1981. See the end of O.C. 4:88.