Utterly Mad

Nah the Creation Engine isn't Gamebryo

It's literally the same engine with some polish. The only noteworthy difference is sort of different scripting system which is also obtuse and frail as fuck in comparison to FO3 version. Oh, and a hardcoded limiter for creature skeletons that makes it almost impossible to implement new ones.

If they give the option to turn it off, that would be great.

I bet it will be the first mod after making dog non-essential.
Well, granted that Bethesda won't try to pull some new horseshit regarding modding.