If testing goes ahead with the G line, the gates will go down early and stay down for hours at a time or all day for at least a year.
Northbound and southbound traffic for motorized vehicles will be stuck in standstill for miles, like what happened with the line to the airport. 
There has been discussion to remove the crossing gates altogether like Downtown where RTD Light Rail Trains travel the wrong way on one-way-streets, speed, run red lights, injure and kill with absolute governmental immunity.
I am a photographer that got hit by an RTD Light Rail Train that ran a red light.
I suffered multi-trauma injuries and RTD refuses to pay any hospital bills or needed follow-up surgery.
RTD is never faulted for injuries or death caused by the politically corrupt Design and  Operation of RTD commuter trains.
To see exactly where and how I got hit by an RTD commuter train that ran a red light, Please Google: RTD Light Rail Train Running Red Light