One of the worst maintained strech is BBK - FD - BSB section not fit for more than 80 kmph but still SFs like Kaifiyat and others run at 100 or 110 kmph awaiting big derailment anytime. This incident could have been one of them if driver wasnt alert.
alognwith this, some of the other stretches of NR, are
1) ROZA-Sitapur section (quite busy)
2) Unnao-Balamau section (not that busy)
3) Balamau-Sitapur section (least busy)