Pete,
Good question, I wondered the same thing. After all why would you bend a tab OUT when you know that the tail cone needs to fit INTO the fuse? If you'll notice, that tab is in the middle of the radius. If you don't bend that tab out, it will create a relatively large gap between the fuse and that particular tab.
Bending the tab out closes the gap and makes it easier to rivet without having to find a way to push the tab out for proper "nesting" and to eliminate a gap.
Hope that helps.
Fred