In my view the gold standard is less than 0.20mm for radial true and 0.25mm for lateral true. Any such transitions would also need to be gradual. Working carefully, this can be easily achieved with a dial indicator setup. This also assumes even (within 5%) spoke tension all around (on the same side for rear wheels) so they can stay that way. Even spoke tension is much more important than a perfectly true wheel.

Achieving this degree of exactness can take a fair bit of additional time and most builders would not consider it economic. However, when I put wheels together for myself I take the time and do it right. I estimate that it takes me 5-7 hours per set from lacing to finished tolerances. At least 4 hours of this is evening and fine tuning.

I would not recommend using a truing stand for dish unless you calibrate the stand immediately prior to use as they often go out.

I do agree with the post above that most tubulars (especially handmade) are running out by a factor of 10-20x that the poster cites. So, is it worth it then? I say yes because the brake calipers touch the rim but never the tire so brake throb can be eliminated.