Parshat Lech L'Cha
In 16:15 Avram and Hagar have a child and Avram names it Yishmael.
Rashi says that Avram named it Yishmael, which is the name the angel instructed Hagar to name the child, despite his not having known of that conversation. Rather Avram selected the name via Ruach HaKodesh.
Why does Rashi have to come on to that reason? Why not just say Hagar ran away, came back after her revelations, Avram asked her what happened and she told him about the angel and what the angel had instructed them to do? If Avram had been told that the angel had told her to give that name, he for sure would have done so.. So why come on to an explanation of Ruach HaKodesh when there is a very valid normal explanation?
According to Rashi Hagar clearly did not tell Avram of the revelation. Maybe Avram did not even know she had run away.
It could be that Hagar never told Avram about it because she did not want to "rat out" Sarai as being bad or at minimum the source of strife that caused her to bolt. She preferred to take the chance of not naming the child the name the angel had instructed rather than rat out Sarai by telling the story.
Any better answers out there?