The little Mitzvah

 

The Mishna Verurah (104sk 9) writes:   "People consider פתיחה before אבינו מלכינו  as a little Mitzvah." (“שהעולם חושבים זה קצת מצוה") " It seems,  1) That it is not really a Mitzvah just people consider it as a Mitzvah. 2) That only the Pesicha of אבינו מלכינו people consider as a Mitzvah and not all the other Pesichos.