Which, depending on where you are in the building..and how the monorail schedule is running....is about how long it will take you to walk over to the Magic Kingdom.
We usually walk to MK from BLT and take the monorail back. We are usually excited to get to the gates in the am, so we don't want to waste any time riding the monorail around to the other resorts.
We walk both ways - it takes longer to wait for a monorail, ride to CT, walk back over to BLT than to just walk back. It's a pretty pleasant walk, outside of crossing the road.