For myself I still like the idea of one side at a time so I can check for even bending. Having had too many run ins with Murphy over the years I tend to think in terms of "belt and suspenders" ways in order to cut off any troubles before they occur. And that explains why I'd go one side at a time.

Do we need this level of accuracy? I guess it depends. We see enough threads around here from folks complaining that their bikes won't ride hands off easily. An out of true frame would cause such troubles. So perhaps there is a need for better accuracy. Or at least a way to check the accuracy after the bending is done so any minor corrections can be done.

As for wheel placement consistency I think you may be underestimating how well a good eye can center the wheel where it passes through the chain stays just behind the BB shell. I've never had any issue with getting that good to within a mm or less. Mind you after years of shop work folks can develop fairly well trained eyes for this sort of thing so maybe it's easier for me than some others.