The original description uses the value 12 because of the prior value of 2 hours, whereas you seem to just have N generals and no such hourly time from which to derive 12, plus this:
The existence of the 12-block chain is proof that a majority of them has participated in its creation.
Why is the existence of 12 verifications proof that a majority of N have participated?
The existence of the 12-block chain is proof that a majority of them has participated in its creation.
Why is the existence of 12 verifications proof that a majority of N have participated?