Anyway, the letter let Nobumori choose to either go into seclusion for the remainder of his life or regain his honor by making achievements at the risk of his life, and so the banishment was his choice and it should be taken into account that Nobunaga did not banish him without any choices (Toshiie MAEDA regained his honor by making an achievement).
どちらにせよ、折檻状は命を惜しんで隠棲するか命を懸けて功績を挙げ挽回するかという道を選ばせており、少なくとも追放されたのは信盛自身が選択したことで信長自身が問答無用で追放したのではないことを考慮する必要がある（ちなみに前田利家は功績を挙げて挽回したくちである）。