Decision delay is, many times, a result of the failure of a group of people to converge in time. Those "exactly right" people require a lot of information in order to make the decision. High performers we've worked with over the years require less information and therefore less time.
General Colin Powell talked about having to make battle field decisions with only 40% (or less) of the information available. Waiting, in his case, for the perfect convergence of information quality and quantity was rarely an option. This is true today in most corporate settings as well.
The trick we have found in rapid convergence is to properly delineate the problem. The way the problem is structured can represent 90% of the effort. Rapid convergence also requires a simulation vehicle where decision alternatives can be explored, test, argued, and resolved with groups of people (i.e. the stakeholders). This is similar to how a fighter pilot trains for battle in a flight simulator, testing and experimenting before actually climbing into the real cockpit. Teams need a similar mechanism.