The first involved taking all sorts of situational data from various sources in an airport, e.g. radar systems with their own binary formats, and combining them with the work of a postgrad researcher who had come up with an algorithm to optimise when pilots should turn on an aircraft's engine in order to save fuel and cut emissions.

The second involved managing 3G dongles on fleets of laptops, tracking and sending alerts on their usage and billing info in realtime, back in the days when business users would accidentally run up £10,000 bills abroad.

If at any point in the first half of either of these projects I'd been asked to come up with an estimate for the total amount of work, it would have been wildly inaccurate. Each project had both low and high level surprises at every turn that would have just compounded to blow those estimates up. There is basically no significant way in which one informed the other, even though parts of the systems used similar event sourcing architectures on the exact same server-side stack, and were done for the exact same startup which broadly offered real-time systems to utility companies of various sorts.

It's entirely possible that there exists a breed of programmer who could have estimated these projects in their entirety, much earlier and more accurately than we did, but I've never met them, and I'd rather work in places that didn't compel people to.

I've known and worked at other places where basically any software methodology would (and did) work, but I certainly don't think it's rare (as you seem to suggest) to find yourself at the other end of the spectrum.