Let me preface this by noting we're doing some modeling of wait times at the parks. So what I'm about to say IS NOT NERD TALK OKAY?
Last week we counted just under 400 people get in line for TRON at the start of Early Theme Park Entry. That is, ~400 people spent their entire 30-minute ETPE benefit on trying to reduce their wait at TRON.
For reference, we think TRON's hourly capacity averages around 1,300 per hour (1,200-1,500 is typical). So the 400th person in that initial rope-drop group was going to wait just under 19 minutes to ride.
Of course, the next question is "Does this reduce the amount of time you spend in line over the course of the day across all attractions?" The answer to that is "it depends on what else you want to ride." But I suspect the answer is no.