It's as good a technique as any other. If the headstock is nipped up snug there will be no significant loss of accuracy - and if the finished piece is within tolerance then it's accurate enough. As for swarf wearing the sliding surfaces, that applies to al the sliding surfaces, but it doesn't seem to be a major problem.
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I have seen NC lathes feeding the bar stock through the chuck (collet, or whatever) while turning the diameter with a stationary tool. There must be a bit of cunning going on the get the grip slack enough to feed but tight enough to get sufficient accuracy, and keep the bar rotating, although I can think of ways to do that which are probably simple on a sophisticated modern machine.
