tochacha vs. kelala - parshas ki tavo

Chazal tell us that Ezra made a takana to read the parsha of “kelalos” before Rosh HaShana so that the curses of the old year are finished off before starting anew (Megila 31). Based on this takana, even when the krias haTorah followed a tri-annual cycle, Parshas Ki Tavo was read immediatly prior to Rosh haShana (see Maharat"z Chiyus). As noted on Friday, the difficulty that anyone with a calendar will notice is that we do not read Ki Tavo immediately preceding R”H, but insert Parshas Nitzavim in between! Rabeinu Nissim (quotes by Tosfos) explains that Parshas Nitzavim also contains negative elements that must be read before R”H to fulfill Ezra’s takana. Tosfos disagrees and writes that Nitzavim is not part of the kelalos, but is a break so we do not end the year on a completely negative note. According to Tosfos, there seems to be a fundamental difference between the negative elements in the keri’ah of Ki Tavo and the negative elements in the keri’ah of Nitzavim: Parshas Ki Tavo is called a parsha of “kelalos”, but Parshas Niztvaim is simply tochacha (see R’ Ya’akov Emden’s notes on Tos). In other words, the focus of Ki Tavo is portraying the terrible destruction that can emerge when society becomes steeped in cheit; the focus of Nitzavim is on reproof, with the destructive consequences mentioned just as a motivation to improve. We commonly refer to Parshas Ki Tavo (and Bechukosai) as the parsha of the “tochacha”, but based on Tosfos' reading, the gemara is precise in its use of the term “kelalos” and not tochacha when referring to the parsha.