How should I use BestBikeSplit to pace a long hillclimb at altitude?

Does anyone have experience, good or bad, with using the Altitude Power Adjustment feature in Best Bike Split? I’m interested especially in hearing any real world results of creating pacing plans based on the predictions generated by the feature. I wonder how realistic this feature is, when pushed to somewhat extreme inputs.

I’m planning to do the Pike’s Peak Cycling Hill Climb event.
With an event starting location being thousands of feet about my training elevation, and the finish of the event being over 14,000 feet, I can imagine even a small error in estimation could yield a substantial difference between predictions for pacing and real life outcomes.

Before BBS had the Altitude Power Adjustment feature, people were breaking hill climbs into segments, and using their own estimates for ftp reduction for the altitude range of each segment. Would this be, perhaps, a smarter approach for a pacing plan, or at least a decent “sanity check,” rather than relying fully on the Altitude Power Adjustment for what might be kind of an “edge case” use of the feature?

Has anyone got a story about using either(or both) of these strategies for creating a pacing plan of over 2 hours in length?