The thing making this show so frustratingly awful is the stopping to let them get away thing is just done so badly. In this particular episode for instance when the guy first shifts, he stopped so he/she could shift and talk, but he couldn't know he was going to stop and change nor talk so why did Barry stop 10 yards from him rather than pile into him. It's just awful tv, the speed is difficult to work around and was always going to be a problem. But even there all that needed to happen was he went around the corner and stopped because he couldn't see him. Then later on they reveal it's a shifter as a camera catches the change around the corner. I mean even if he did catch him but the shifter escaped his grasp by turning into a child, slipping out of clothing and running into a subway, the shock of it happening might throw him off. That is plausible, but stopping 10 yards away just so he could watch them shift... is truly awful direction/writing.
An episode or two ago with the second weather guy, he's draining the power out of the room then it's stopped.... THEN it cuts to the guy turning around, but still upstairs still would have taken ages to get out of the building. Make the device shock Barry and knock him over, make it take longer, show the guy running as soon as it was over. Instead it showed him turn to run after the device is done and Barry was completely free to chase him.
Almost every episode it's just crap directing and/or writing, when 5 seconds thought would make an escape more plausible instead they make every single bad guy idiotic and easy to catch within 20 mins of the episode. Whole thing is painfully painfully frustrating to watch. if it wasn't for the Arrow and the crossovers I'd likely have given up very early, as it stands I'll watch a few eps of season two.. presuming there is one. Without a huge improvement I'm giving up on it.