If you have been in the parks on Level 10 days, please answer my question about how you toured the parks on those days ?
It depended on the park but it always involved paper FP's. It depended on who wanted to ride what, which attractions had FP's that weren't connected to the rest of the FP system, single rider versus family, what elements of EasyWDW suggestions we felt were applicable, and how fast a Dole Whip can melt.
And ultimately, the largest component of that strategy involved the old paper FP's which you can't get anymore.
So now, considering the current circumstances as we all know them to be, if someone who had never been to WDW before was considering going to a park on a level 10 day, my first piece of advise to them would be: Don't.
Because this entire hypothetical is a bit ridiculous to begin with when out of 365 days a year, how many are "Level 10" ????
What most people want to know is how to best plan their day with the new FP system under a variety of but often common conditions.
Telling them to "show up early" is just part of it and it may not even be a valid recommendation if the park they are going to has morning EMH or doesn't or has a party that night or doesn't or they don't have park hoppers or they do or a wealth of other factors.
What I see developing given the current state of FP+ is a strategy that shifts importance from getting their early to park hoppers and requires both.
So the advice I would currently give to someone who has not been to Disney and is considering going under non-extreme crowd conditions who would like to utilize their FP's where they get the most bang for the buck figuratively speaking would be to go to the most-recommended park in the morning, ride SB, get out of there before the crowds hit, go to the park where you reserved your headliners, walk past the long lines to enjoy them with your FP's, then stay or go to the park you want to see fireworks and parades in the evening.
And that requires Park Hoppers.