I mean... are you bobbing and weaving your head while rolling your tongue or what?
I get that CRTs aren't perfect, but I'm not sure how else to reproduce what you're calling "flicker".
perhaps was 60hz interlaced. I had memories of my first CRT monitor only allowing to do 1024x768 in interlaced and doing a very obvious flickering. But was flicker free at 800x600 and lower resolutions.