Interesting. I think it's the wrong test, though. (I mean, look, it's hard to get data on actual software engineering. They got actual data, and they published it. It's more than most people ever do.)<p>I think the real test would be to do the same experiment, but not with a prototype. It would be to write a finished program, <i>and then maintain it for a decade or three</i>. (But of course, nobody's ever going to run that experiment - it would be too expensive, plus the time is too long for the "publish or perish" world.)<p>The point is, more matters than just "how fast can I develop". How fast can I develop code that can be maintained for a long time by other people? How hard is it for them to maintain? How does the choice of language affect that? How does <i>how fast it was developed</i> affect that?<p>In the real world, speed of development is only one variable, and maybe not the most important one. (And, yes, I'm complaining about the data being inadequate, after noting earlier how rare it was to get data at all...)