You really can't seem to break away from telling me about how it was.
Sorry, but you are the one who is missing the point (and the math) here. The reason that my explanation looks like the way it
was is because even if everyone used FP-, there would be no visible change over the way it used to be
in the early morning hours of the park. It is your math that needs re-tooling. You seem to believe that all 38,000 people would teleport themselves into the park at exactly the same time, and all people would be in all places at the same time. But people would trickle in, and the early arrivers would get the same experience under either the "half use it" or the "all use it" scenario.
If you arrived at RD and pulled a FP for Soarin' at 9:05, your return time would be around 10:00 and at that time you would get a FP for TT. This wouldn't change irrespective of the intent of the other 37,999 people. It doesn't matter if 20,000 people or 38,000 people
want to use FP-. In order for them to impede my process,
they have to be ahead of me. The people who make RD will get early FPs for Attraction A, and will be first in line to get their second Fast Pass at Attraction B. The only way that their plan can be foiled is if enough people forego a FP at Attraction A and go straight to Attraction B to get a FP there, draining that system dry. And here is where your math fails you. There simply cannot be enough people arriving at the park early in the day to go to Attraction B to drain that system dry. Remember that I am ahead of all (or most of) the people who pulled a FP for Attraction A. Thus, my window for my second FP opens before theirs so they cannot leap frog me. Assuming that I get to the second FP machine 2 or 3 minutes before that window opens up, few of the people who also pulled a FP for Attraction A can beat me to the punch. So the only people who can stop me from getting the second FP at around 10:00-10:30 are people who go straight to Attraction B to get a FP there. The machines simply could not spit out 13,000 FP in an hour, even assuming that 13,000 people lined up to get them. And that would never happen. Sure, 38,000 people might go to Epcot on the day in question. But how many will be in the park by 10:30? 20,000 tops? There is simply no way that 20,000 people can drain two major attractions dry in an hour, even if every person intends to use FP-.
Your "math" presupposes an the system's unlimited ability to dispense FPs. But there are physical limitations which prevent the well from running dry in half an hour. It is very much like the "American Idol" voting phenomenon. No matter how disparate the two finalists are in talent, when the voting was done solely by phone, the vote was always 49.5% to 50.5% or thereabouts. Why? Because of the physical limitation of the phone system. 10,000,000 people might have been in "phone queue A" to vote for contestant "A", and 7,000,000 people were in the "phone queue B" to vote for contestant "B". But if each line of the phone system could only process 1,000 calls an hour, at the end of 100 hours of voting, contestant A would have 100,000 votes and contestant B would have 100,000 votes. A virtual tie. But that does not reveal the true nature of how people wanted to vote. So too with Fast Pass. It doesn't matter if 38,000 people wanted to use FP- or 20,000 people wanted to use it. In the early hours of the park's operation, the same number of Fast Passes would be disseminated in the first 90 minutes of operation unless Disney brought in 5 times as many machines to spit out tickets. As long as you got a FP for the more popular attraction first, you will get one for the second most popular attraction.
We don't need to look any further than TSM to see this in action. That is the only ride at WDW where a legitimate queue ever developed for a FP. As popular as Soarin, Space Mountain, Everest, Rock-n-Roller Coaster, et al. are, you never had to wait behind more than 4 or 5 people to get a FP for any of those rides. So let's double the entusiasm for FP- and now you'd have to wait behind 8-10 people. That wouldn't shut you out. But let's get back to TSM because that is where the line developed. If there was 100% interest in getting a FP for that ride, it is absolutely possible that someone who went to RnR first, rode that ride, then went to ToT and rode that ride, and then got in line for a FP for TSM could get into such a god-awful long line that they would get shut out. I will absolutely grant you that. So what would be the solution? Go there first. Everyone who decided to go to TSM first to get a FP would get one as long as they were among the first 15,000 people through the turnstile. Early arrivers would get what they wanted. So now you have your FP for that ride and are shut out from getting another FP for two hours.
But so is everyone else. Who is going to stop you from getting your FP for RnR? No one, because they also have a TSM FP and are shut out for two hours. The only way this fails is if 15,000 people arrive early at DHS, decide not to get a FP for TSM, and instead queue up for a FP at RnR and drain the system dry in 2 hours. That could not happen and would not happen. That would require 30,000 people all passing through the turnstiles at RD. Never happen. Even if 30,000 people arrived for RD, there still has to be an orderly queue of people getting through bag check and the turnstiles. The first people in the park would probably have their 2 FPs in hand before the 25,000th person actually got in the park. Sort of like the people who start at the back of the pack at the New York Marathon. The race starts for all people at the same time, but the people at the back take an full hour just to get off the Verazzano Bridge. The people at the back of Rope Drop are simply not going to be grabbing FPs to the detriment of the earlier arrivers.
The whole point to FP+ is to offer a level playing field for later arrivers, park hoppers and people who want to do something else with their day at 9:00 a.m.. But there is no argument that one can posit and prove that would show that FP- wasn't better for Rope Droppers. Would 38,000 people trying to use FP- make FPs harder to get at 2:00 p.m.? Sure. Would it make more rides run out? Sure. But it wouldn't make TSM run out any earlier. Its machines were already maxed out. As long as you were one of the first 15,000 people in line to get a FP, and it took 2 hours to dispense 15,000 passes, then the same 15,000 people would get one and they would get theirs in the same 2 hour span. The fact that the line is longer doesn't make the machines spit out the tickets any faster. So before you might have had 20,000 people in line to get 15,000 FPs and 15,000 got them over the course of two hours and 5,000 people were disappointed. If 38,000 people lined up for 15,000 FPs, those same 15,000 would still get them over the course of two hours and you would have 23,000 disappointed people. You have increased the number of disappointed people, but you have not altered the touring of the 15,000 people who got their precious FP. As long as you commit to being one of the first 15,000 people you get your FP and then move on to the next attraction. Does all of this look the same as the way things were? Absolutely, as long as you are an early arriver. And that is the whole point. The first person in the park cannot have a different experience if there are 10 people behind them, 15,000 people behind them or 38,000 people behind them. The number of people behind you does not alter the view that you have ahead of you.