The 1971 conflict was largely omitted because the blame was put on India for invading an independent country. The reasons for "not respecting the people's mandate" has been explained here by me. This was not a military decision alone. None of the mainstream western wing's political parties wanted Mujeeb to become the PM. They all pleaded with Yahya Khan to not give the reigns of West Pakistan to Mujeeb. The slogan attributed to ZAB of "Hum yahaan, Tum wahan" (Us here, You there) was coined not by the military leadership, rather by the western wing's polity. So the denial of mandate to AL/MuR was not just the miliary's call, it was a collective call made by the sons of the soil in the western wing of Pakistan.