We used to do quick align on every turn-around, most probably a hang up from the old 737-200. What do I know.
But some 5 years ago we quit doing it.
As I was flying out of the Canary Island on trips from 4 to 6 hrs I started looking at the drift of the two basic IRS positions as we turned the aircraft around and got more coffee.
Most times they were out with one to two miles after 6 hrs, seldom in opposite directions. So we are talking a drift on the 737-800 of less then 1/2 a mile normally. The odd time it was more then the 3 miles and a FMC warning would trigger on the ground.
If I am not mistaken the IRS position auto updates on TOGA selection on T/o on the 738.
12 nm/hrs drift sounds like a real bender on a Saturday after payday!?
Happy Navigating