At large organizations it is often the case that the amount of power you wield is determined by the number of employees that report to you. This creates an incentive to bring on new employees whenever you have the budget and to avoid layoffs of your people wherever possible. So even though Dan (the estimator) isn't really needed he still serves to increase some middle manager's power.

At organizations like this you'll often have "re-orgs" where a few people are laid off (relatively speaking) but the "managers that matter" (those with the most power) come out having the same number of people beneath them. It will seem completely arbitrary to the people at the bottom of the org chart why their boss's boss's boss changed but the truth is that it happened because that guy used his influence to finagle the org chart in such a way as to keep the same number of reports.