That said, heck yeah, I made the window for both. I am a trained professional, after all. ;^)
If they are going to enforce windows, however, I think one of two changes need to happen:
1. Selection of windows. Either have riders be able to select a window when getting their Fastpass at the attraction, or have a centralized distribution center where all passes for the day can be obtained at once. In both cases, each window has a set number of passes and once a window is fully booked no more passes will be distributed for it. If there was a centralized distribution center, I would add the restrictions that a. only one Fastpass for any attraction may be obtained per day and b. windows must be a set amount apart (say one hour between the end of one window and the start of the next). This would keep guests from taking too many Fastpasses at once. In either case, once tickets are collected they may not be exchanged unless a ride goes down (in which case they will either be good the rest of the day at that attraction if the breakdown occurred during the window or can be exchanged for a pass to another attraction if the ride will be down all day).
2. Validation stickers. If something happens that interferes with your window (slow service at a restaurant, unexpected trip to first aid, stuck on a ride, etc.), you would be able to get a validation sticker that will allow you to use your pass after the window has ended. Also, in the event of a ride you hold a Fastpass for being closed for an extended period of time, it would be nice to be able to transfer your Fastpass to another attraction if you wish (with a separate validation sticker that can only be obtained at the closed attraction, of course).
I could get another Tequila shot in Mexico pavilion but I have to leave to catch my Test Track window.
I think this claim that "late fast pass users are clogging up lines" is a lot of BS or hyperbole. It's not that hard to figure out how to distribute between fast pass and stand by capacity. Cast member's have recommended us to come back later with our fast passes when one of the sides of Sorin' is down.
However, this will make the RSR Fastpass line.........
During the mornings, when lines are shorter, there is less reason to get a Fast Pass **if the return times are enforced** because you don't save much time versus being in the standby line. The lines tend to be longest in the evenings, especially after parades and nighttime shows, and the demand would be greater for Fast Passes around those times.
The logic of the Fast Pass system is that a ride's Fast Passes are used up in sequence throughout the day until all Fast Passes have been distributed.
Those who have the knowledge that return times were not being enforced could "game the system" by collecting Fast Passes throughout the day, and then using them during popular times. This would force the standby line to slow considerably for a given ride because the allocated number of Fast Passes for a given hour, say 8-9 pm, were being far exceeded by people who had collected them for earlier return times.
I don't think that most people realize that when the system was rolled out in 1999, Disney told the media that the idea was for visitors to collect their pass and then stay in the general area of that major attraction and shop, eat at a restaurant, or go on a smaller attraction with a shorter line. Visitors would benefit by being able to do other things than spend time waiting in line. The unspoken part of the equation was that Disney would profit from being spending money in shops and restaurants instead of standing in lines.
I'm not claiming that is the motivation for enforcing the return times. It's been reported by Robert and elsewhere that implementing the Fast Pass+ and Next Generation reservation systems requires better control over how visitors were using the limited number of Fast Pass slots.