A useful little addon I thought I’d share, given the new blender can now split normals without harming actual geometry. It removes any old edgesplit modifiers, and replaces them with autosmooth! The default autosmooth angle is 176 degrees. (So only marked sharp edges will be made sharp), however if anyone needs it I will put a small menu in that lets you change it!
To use; hit space, type ‘convert’ and the option pops up. It will apply to all selected objects.
Requires blender 2.70.6 or above