Double it is basically the engineering mantra -- The problem is when is occurs in big organisations and/or projects. The doubling can be compounded as the estim

Double it is basically the engineering mantra -- The problem is when is occurs in big organisations and/or projects. The doubling can be compounded as the estimates trickle up. I've seen reasonable estimates of 10d suddenly explode into 40+d once it makes it into upstream project plans. Best thing to do is invest in metrics, and to revisit your estimates after the fact (nobody ever does this).