When I showed up to the ride around 4 o'clock this afternoon, I entered the queue like normal and noticed, as others have pointed out, several smaller riders not being allowed to ride after being seated and not having their thighs touch the restraint.
When I came back to the ride around 6 o'clock, there was line at the entrance of the queue. Apparently, in that two hour span, a new policy had been created that all guests must try the test seat before entering the queue. When I returned around 6:45 and 7:45, two different attendants were doing the same thing and also said that mandatory use of the test seat was a new policy being enforced for all riders.
I noticed that several high ups were hanging around the ride all day, so I assume this decision came from them sometime this afternoon. I actually kind of liked this system, as it should nearly eliminate the frustration of waiting through a long line only to take the "walk of shame," since riders who are too large or too small can be turned away immediately. This also makes loading more efficient since these guests don't need to be removed from the train once seated. The location of the test seat in the secluded U-turn before the official queue entrance also kept the line fairly organized.
While this system is really more of a "band-aid" fix that merely mellows the problem rather than solving it, I appreciate the park's impromptu new approach to cutting down on Twisted Timbers' unfortunate accessibility issues.