Actually yes, some people have successfully created the final version of the equipment from the Senior pieces. And not just the GM staff.
I know of atleast one one star (Pink) AA that was made and a lot of barok shields were made. All from the Pieces.
I know it may seem unfair but it's really about the same chances of getting them from the boatyard. And it's another way for non-AP users to get a rare item so I think it's a good thing. It may be a low % but it's still better then nothing.
I hated failing my Pink AA T_T and I also failed my barok shield but oh well. I have more chances to try.
By the way, I know this is in the wrong thread but I think Daily Tasks for junior pieces would be awesome. Bounded of course but still awesome.