Just something to consider:
"There will be other amusement attractions that have unique designs and features which are not adequately addressed by the guidelines. In those situations, the guidelines are to be applied to the extent possible."
So, for example, DCA rides, all of which were built after the ADA was adopted in 1990, do not always allow a guest to remain in a wheelchair. 4 of bug's land attractions require guests to transfer from wheelchair/ECV. A total of 13 attractions out of DCA's 30 require guests to make such a transfer.