I think bhishma did a big mistake by not disobeying his father and taking a lifelong vow of celibacy. Had he confronted his father at the right moment this whole war could have been stopped.
Was it so important for bhishma to serve his father's lust ?
If he was so wise couldn't he identify that his father was running for lust which can bring devastating consequences?
Does Krishna in any of the scriptures (or any other scriptures) mention that we should not obey our parents blindly?