I don't watch them, haha. I don't watch fights from before 2000 at all.
I just fast-forward through fights looking if no rd is missing before I save it. That's easy when you have TV giving you round number on the screen. If no, I look at boxrec at how long the fight went and just count the rounds "manualy", looking if round goes 3 minutes too.
It doesn't take all that much time, man.