My point was that it's all but impossible for any rollback to be entirely risk-free in this sort of situation. If everything was understood well enough and if everything was working to spec well enough for that to happen, you wouldn't be in a situation where you had to decide whether to make a quick rollback in the first place.
I'm not saying that the decision won't be to do the rollback much of the time. I'm just saying it's unlikely to be entirely without risk and so there is a decision to be considered. Rolling back on autopilot is probably a bad idea no matter how good a change management process you might use, unless perhaps we're talking about some sort of automatic mechanism that could do so almost immediately, before there was enough time for significant amounts of data to be accumulated and then potentially lost by the rollback.
I'm not saying that the decision won't be to do the rollback much of the time. I'm just saying it's unlikely to be entirely without risk and so there is a decision to be considered. Rolling back on autopilot is probably a bad idea no matter how good a change management process you might use, unless perhaps we're talking about some sort of automatic mechanism that could do so almost immediately, before there was enough time for significant amounts of data to be accumulated and then potentially lost by the rollback.