There is a letter written by Chosokabe Motochika to Akechi Mitsuhide's retainer Saito Toshimitsu just before the Honnoji Rebellion in June 1582. Akechi Mitsuhide had a good relationship with the Chosokabe. Mitsuhide tried to protect the Chosokabe's domain from an attack from Nobunaga. The Chosokabe did not want to pick a fight with Nobunaga since it they were not strong enough to handle Nobunaga's army in battle. In the end, it seems that the Chosokabe would give in to Nobunaga's demands without fighting. This actually makes sense. You know the old saying, "Never fight a losing battle." Now the big question: Did Mitsuhide know about the Chosokabe bowing to Nobunaga's demands? Who knows.
There is another theory out there that Mitsuhide knew about the letter. At first, Nobunaga and the Chosokabe deal was not going to work out. However, Nobunaga changed his mind and wanted to work with the Chosokabe. That being said, both Mitsuhide and Toshimitsu planned a deal on their terms, not on Nobunaga's. This letter mystery still and will be debated for awhile.
Nobunaga no tame!