I participated in the trial program these last few months being a Global Entry member.
The concept does have validity, however I hate to say it, if its too broadly expanded it will likely not end up being much faster or different than the general security check.
While in theory the TSA
will allow participants to avoid some of the more laborious checks - to keep people guessing and deter the expectation that you will always be afforded the reduced screening my experience has been that less than 50% of the time at participating airports are you able to truly enjoy this. One thing I noticed, is that at least during the trial, check points were not always set up for this expedited handling - seems like they only did it for a few hours at a time at some locations.