I
tend to believe that a hearty practice of GTD helps teams achieve more. My team recently had a series of related decisions to make and we had struggled to come to a conclusion for some time. I decided to put Getting Things Done into play and accomplish the following:

Change your context. Sometimes it helps to change your physical location when making a decision. Booking a conference room instead of the ordinary meeting space might pay dividends for your group. Context can also include looking at long range plans as opposed to the details of daily life at work. Meeting at different times about specific things is a lot more productive than trying to hit everything in one sitting.

Close the open loops. This is perhaps the greatest skill of leaders in addition to setting vision for the team. Forcing (gently- possible?) the group to make a decision is absolutely essential. GTD is certainly applicable in this regard. Any loop that is open will come back to you so tackle it early and often. (See this interesting take on whether all loops are created equal)

Remember your runways and landscapes. Your group might be struggling to make a decision because it's too bogged down in the day to day and can't see the broader view. Give them permission to think as big or small as is helpful. When Charlie from sales gets off on another tangent, confidently say, "Thanks Charlie but we'll tackle that at another meeting. Today, we're honing in on XYZ." It works, trust me. (See Patrick Lencioni's take on how teams work)

Accept the fact that your group needs you to have backbone. At the end of the day, after you've invested in your group and they know that you respect them, they still look to you to make a decision. It's as if they are saying, "Now that we've all had something to say, what do you think boss?" Put it out there and don't be bashful about pointing the team in a reasonable direction. You're not about command and control, but about direction and flow. (See David Allen's piece on the Huffington Post in this regard)

The worst thing to do is expect a "good" decision to come from a "bad" process. To the degree that you can set your team up for success, extraordinary things will follow.