Haha yeah they're extreme.
To be honest, i do a bit of everything. The outline of the story would be anchored in three parts, the beginning middle and end. For The Golden Quiche I would let events have more wiggle room since it's a shounen gambit adventure. The only set piece are the definite ending and the middle twist. The journey to get there is drafted, but with some monkey wrenches thrown in to hinder the cast.
For my next professional story though... That involved quite a bit of spreadsheets of detailing a draft of every event to steer to a set ending.