I've read about this several times on RCU for the Laser 3D and the Madness. They serve no purpose, are hard to cover on the Laser, and they actually hamper knife edge, harrier, waterfalls, and elevators. If those 3D flight characteristics are not important to you, then don't worry about it.

I would suggest some 1" triangles or other bracing to help support the last rib because the covering tends to bow it in when you shrink it.

Chuck