FassPass works great for people who only want to ride a few rides a day, and have the time to come back multiple days(or visit multiple times a year) I do not have that luxury. A typical vist for me would be 2 days at magic kindom and one at each of the others, with partial days on arrival and departure to maybe squeeze something in. I also only visit about once every 2-3 years. Last visit we had to skip a couple of rides because we couldn't get fasspasses and simply didn't have the time to wait 100+ min in standby. It was busy but not overly crowded, By contrast I went in 2009 during spring break when they still had the paper fasspasses, which you could only get day of visit. MK was at capacity they were starting to limit who could get into the park and yet we had no problem ridding every ride in the park. most waits were between 30-45 min.
FassPass is working great for Disney, its getting people to plan longer trips. They spend less time in the parks each day and just come back multiple days so they can use fasspasses instead of waiting in standby. Once the fasspass are used many guest will leave to spend more time at the resort (and spend more money) or do other activities around WDW (again more money). The longer they can keep you on property the more money they make, this has always been the goal of WDW. People are stretching a 1 day visit to a park out to 2,3,4 days so they can use their fasspass then leave and do something else (aka spend more money some place else). Fasspass isn't about making things better for the guest its about making money for Disney. Oringally it was about getting people out of lines and into stores (to spend more money), which I don't think ever really worked. Now I feel its more about getting people to plan longer trips so they can uses fasspasses on more attractions and avoid ridiculous standby lines which the fasspasses have created. Longer vacations = more money.
When you had shorter standby lines on capacity days before the current fasspass system then you do now on non cpacity days with the current fasspass system you can't say the only reason lines are longer is because more people are going to the parks.
They have also started to experiment with selling extra fasspass, if that ever becomes wide spread I will start planning more trips to DisneyLand instead or maybe one of the parks over seas......