If your following agile and using level of effort story points, your grooming sessions should solidify stories that the team agrees is complete (fully defined).

If your following agile and using level of effort story points, your grooming sessions should solidify stories that the team agrees is complete (fully defined). If someone is sandbagging, this will become obvious to the team and can be addressed directly. My experience with hours is that management still wants actual cost metrics, so they still need to be tracked.