n0mesorah,
““Rav Moshe never offered reasons to allow””
“Black on white, a large part of his teshuva. Otherwise he would have felt compelled to stop them. And he would have considered the eruv to be Chillul Shabbos.”
No, Rav Moshe only admitted that the Aruch Hashulchan and the poskim would not agree with him. That is why he did not issue a psak din barrur.
