It really depends. If you see programming itself as something that gives you joy - then planning something out of course will remove some of the exploratory joy out of it.

However, there are also times when you have a larger goal in mind - say to build something of immense scale and power. In that sense - the micro level picture takes a backseat.

To me - shipping is the ultimate goal, so I don't see planning as taking the joy away from programming - it only gives me more satisfaction.