What's needed may just be to solicit a wide confidence interval (e.g. "this task will take between 20 minutes and 1 month, and I'm right 90% of the time recently when making such estimates"). You can drop the lower-bound part, probably.
People absolutely should be able to provide a rough estimated amount of effort for a task. The trouble is in using a single point to describe the whole probability distribution. You may be right, in that nobody seems to have a great way of soliciting a probability distribution (or even a single probability) that makes sense. Something like a 70% confidence interval bracketing the amount of effort would be useful, but not sufficient.
I also agree that even if people could describe their beliefs about the required effort rigorously, you have to wonder how much planning/analysis they should spend trying to come up with a tight estimate. An 'outside view' - http://wiki.lesswrong.com/wiki/Outside_view - could give something reasonable in cases that aren't too novel.
I think estimates will never become useless. It's just that we may decide to replace them with "time by which we'll be late only 1/6 of the time", and provide feedback and incentives for people to correct this estimate so that it's, for someone who's experienced in the domain, eventually relatively unbiased.
People absolutely should be able to provide a rough estimated amount of effort for a task. The trouble is in using a single point to describe the whole probability distribution. You may be right, in that nobody seems to have a great way of soliciting a probability distribution (or even a single probability) that makes sense. Something like a 70% confidence interval bracketing the amount of effort would be useful, but not sufficient.
I also agree that even if people could describe their beliefs about the required effort rigorously, you have to wonder how much planning/analysis they should spend trying to come up with a tight estimate. An 'outside view' - http://wiki.lesswrong.com/wiki/Outside_view - could give something reasonable in cases that aren't too novel.
I think estimates will never become useless. It's just that we may decide to replace them with "time by which we'll be late only 1/6 of the time", and provide feedback and incentives for people to correct this estimate so that it's, for someone who's experienced in the domain, eventually relatively unbiased.