[mrfinn]

I guess that neural network has to have the capability of identifying the subject and know in every moment which network is the most capable for that subject, otherwise I can't understand how it could possibly evaluate which is the best answer.

[londons_explore]

Results of this sort of system frequently look almost random to human eyes. For example one expert might be the "capital letter expert", doing a really good job of putting capital letters in the right place in the output.