Tailcone fluting

We're mocking up the two top skins F-1074 and 1075 in the tailcone to drill the stiffeners. On Page 10-12 Step 3 it indicates that the flanges with two holes should be "Heavily Fluted" prior to clecoing the skins. Why? We put the skins on and they clecoed up just fine to the bulkhead and frames. Am I missing something?
Thanks,
Don Oltman

Don't know..

I don't know the answer, but I'm anxious to hear it, because I'm about to begin the tailcone soon enough on my own build. Anyone?

The two hole tabs, which need to be fluted, are on the tightest radius of the skin, and to conform to the skin need to be fluted. Here is how mine looks.