Stephanie is passionate about preservation and was a great guide. Things we would have not done if we didn't book the tour
Know the history of the place that you don't find in wiki or general google search.
Taste tannin :)
Be inside a tree
Get great photos
Drive the windy road
Go to spots that are not listed in attractions page
Wait for the long queue for the shuttle bus
See the places leisurely pace without lot of crowd. It makes a huge difference - when you are the only person in the meadow.
Answer all the silly questions we had :)
We stayed for one more day - she helped plan the second day trip in Kings Canyon and lot more reasons...