I think that seeing the stage kinda takes the fun out of it. Drilling for it either mentally or by doing a couple of “dry run” walks through it will kill the whole concept of being as fast as you can in the circumstances that you’re given and instead makes it into a “routine” so to speak, like being the fastest guy to do a course that’s already familiar.

This is like arguing Track and Field events aren’t challenging because it’s won by the fastest guy to do a course that’s already familiar…

Many types of real-world engagements do allow for pre-planning. In those scenarios, it would be negligent to not have a pre-arranged plan:
https://firearmusernetwork.com/have-a-plan/
https://firearmusernetwork.com/seal-team-six-training/

Outside of this, some shooting events and formal competitions do feature surprise courses. They were routinely held in practical competitive events dating back at least to the early 1960s and are held in certain venues today.

The only reason there aren’t more events featuring surprise courses of fire is logistics. Events are set up and run by volunteers that obviously also want to shoot. Keeping a field or shoothouse course secret requires a range facility that prevents peeking (intentional or by accident) and it must by run by someone (usually a non-paid volunteer) willing to not participate.

Let us know when and where you’ll host something like that for us. :-)

I’ve designed courses that feature a surprise, not-known-in-advance elements that can be fairly shot by the event director and by the people setting the course up. It can be done, and is a feature of TacticalPractical events, but such layouts are not permitted by organizations like NRA, CMP, USPSA or IDPA.