CRT flicker is totally different to LED flicker, the whole room isnt pulsating with light when a CRT is on because it scans, and it has decay like line frequancy fluros do. LEDs are a hard on and off usually, and that means that anything moving has a trail of them, like when you turn on that aweful mouse trail option in windows. Every time going from looking at one thing to another, as your gaze moves between things its so apparant that the lighting is bad its aweful.

In saying that, after quite some time with only nice LCD screens with a stable image on them, going back to the CRT in the junkroom is an assult on the eyes. Will be getting a cheap warehouse LCD to replace it with sometime soon.