“When my Rav shlita was discussing shnayim mikra recently, he said in the name of R’ Chaim Kanievsky Shlita, that being maaver sidrah during chazaras hasshatz is a mitzvah habaa biaveira. I have no source for this, other than his word.”
The source is Orchos Yosher chapter Tefilla Ose 28:
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