Korach Aarons Staff 1973

The Alef Kabbala Group (12 June 07) discussed a discourse taught by the Lubavitcher Rebbe on Shabbat Korach in 1973. It was edited and published in 1990. The discourse discusses the staff of Aaron which blossoms with almonds. This expresses the special power of the Priestly blessing. The discourse explores the nature of blessings given by Priests and Tzaddikim, and the requests to G-d for blessing in the daily prayers. Why is this needed, if G-d has already blessed each person on Rosh Hashanah?