Board Thread:FAQ Board/@comment-210.50.82.157-20141004173645/@comment-3250527-20141028002551

Remember, Slight Slipup was non-canon. Reki doesn't do non-canon (except for that hint of 16.5 that got all the anime fans pummeling each other in the face (in the literal sense) about whether they did the deed or not).

Apparently, Reki writes the script. But I don't know whether he writes the full script or he only makes the dialogue and the studio does whatever the heck they want with it.

(Source: From EE Twitter post, when he stated that he wrote 4 times as much script as needed. Personal deduction.)