increased morale, better customer service, ....highly unlikely.
TSA's insistence on increasing the use of part-time screeners is hurting the organization. TSA expects new people to come to work right in the middle of the day for 20-25 hours a week. Maintaining a second job becomes an impossibility. Bad relations with the employees is going to lead to bad relations with the customers.
I was recently offered full-time split shifts with a two hour break. This works fine for me and most of my colleagues who took split-shift. Most places split-shift means a 4 hour break as mentioned by DCA Screener. This would NOT work well for most screeners. It took some of us 3 years to be offered real full-time employement. Most people just get sick of waiting and quit.