Even with a positive benefit, its a risk, and risks usually follow some form of tracking/escalation policy if they become an issue. Change control procedures will apply to this. I'd assume the next best answer is to let the team take more time to complete everything, however this is something you should avoid. Parkinson's law basically says that any amount of time given for work completion will usually be used up. For example if you give someone an 8 hour workday, but they finish most of the work in 2 hours, they will stretch that last bit of work out to the last hour, this is why you never want to take shortcuts and just throw buffer numbers out there, because each "buffer" you give someone is basically adding cost to it that probably wouldn't be necessary in the first place.