This is totally legal and worked all holiday. Although it's not what Disney or Universal designed the system for, anything that allows you to ride your favourite shows and rides with no queue is okay by me.
1) Arrive at the park BEFORE official opening time. When Universal parks were down to open at 9:00am, I arrived at 8:30am and were in the first five people in the line at the turnstile. Parks were opened at 8:45am.
Disney is different. Where parks were due to open at 9:00am, they DID. Once we were in we were then held back once inside at a rope for 5 minutes more.
2) Not all attractions and show use FP/UE, so pick up the park map whilst your in the queue to enter the park. You can get them from the ticket window (all guest relation desks are inside the park) and in some cases from the turnstile.
3) When allowed into the park target the FP/UE machine of each of your favourite rides in order. The first FP return times (advertised above the machines) will be between 10:00 - 11:00. In some cases, they were as late as 11:30. Usually when you obtain a FP/UE, your limited to one per admission ticket until the start of the return window expires. Subsequent attempts to obtain a FP/UE usually results in a refusal ticket being issued. However, if you are the first to gain FP/UE for an attraction or show then there is no such restriction. For The Mummy I was able to get five FP per ticket. Repeat for the other attractions that you want to attend.
Once obtained, ride at your leisure. To fully utilise the passes, return towards the end of the return window on the ticket. When I done so for Spider-man for example the queue was over an hour wait, yet my Family got to ride 3 times in a row, until we got fed up and gave some of the FP/UE tickets away to other people.
The above worked at Universal Studios Orlando, Universal Islands of Adventure, Animal Kingdom and EPCOT. It did not work at Disney MGM Studios or the Magic Kingdom.
The latest time it appeared to work for a FP/UE return was 11:30am.
What we found was that if freed us up by Noon to enjoy the lesser attractions and shows, which had little queues for the rest of the day.
Our longest wait in line all holiday was 15 minutes. When at one point, queues for Dinosaur at Animal Kingdom reached 1 hour 30 minutes, yet I got to ride it five times with no wait, I had one content and chilled family
Trev