> I would guess that the majority of these people would have been using 15-19" CRT monitors, and mostly single displays.
I doubt that this is the reason. On a CRT I prefer bright text on dark backgrounds because it minimizes visible flicker. Where the screen is dark on a CRT, the beam is simply off. This becomes especially important if the monitor has low refresh rate and/or fast phosphor. I think that it's for this reason that a lot of (actual) terminals have really long afterglow phosphor and use bright text on dark backgrounds. It's basically a prerequisite to use them regularly for any extended amount of time. Newer CRTs improve the situation considerably, though, with much faster refresh rates to compensate for the short afterglow necessary for media like games and video.
Overall I think that using CRTs is more exhausting than LCDs, even taking into consideration the typical size of a computer CRT display compared to a modern office dual LCD setup. After a couple of hours of use of a 15" 2002 CRT my eyes feel dry and sandy, and the problem is exacerbated by bright screen content. Also, my LCDs (at home and at work) are not nearly as bright as my CRTs.
On LCDs I tend to use bright backgrounds in daylight because it seems much easier to read, and the screen doesn't need to be so bright. In the dark, I use dark backgrounds because bright screens easily become the brightest thing in the room with little natural lighting. In practice this means a bright theme at work and a dark theme at home.
I can't wait for paper-like unlit desktop displays with fast refresh rates. IMO it's the most important step for improved computer ergonomics. Then we can fully embrace natural lighting e.g. during summer time office hours, which is healthy for soul and body and easier on the eyes than basically staring into a lamp. Also potentially a lot more energy efficient.
I doubt that this is the reason. On a CRT I prefer bright text on dark backgrounds because it minimizes visible flicker. Where the screen is dark on a CRT, the beam is simply off. This becomes especially important if the monitor has low refresh rate and/or fast phosphor. I think that it's for this reason that a lot of (actual) terminals have really long afterglow phosphor and use bright text on dark backgrounds. It's basically a prerequisite to use them regularly for any extended amount of time. Newer CRTs improve the situation considerably, though, with much faster refresh rates to compensate for the short afterglow necessary for media like games and video.
Overall I think that using CRTs is more exhausting than LCDs, even taking into consideration the typical size of a computer CRT display compared to a modern office dual LCD setup. After a couple of hours of use of a 15" 2002 CRT my eyes feel dry and sandy, and the problem is exacerbated by bright screen content. Also, my LCDs (at home and at work) are not nearly as bright as my CRTs.
On LCDs I tend to use bright backgrounds in daylight because it seems much easier to read, and the screen doesn't need to be so bright. In the dark, I use dark backgrounds because bright screens easily become the brightest thing in the room with little natural lighting. In practice this means a bright theme at work and a dark theme at home.
I can't wait for paper-like unlit desktop displays with fast refresh rates. IMO it's the most important step for improved computer ergonomics. Then we can fully embrace natural lighting e.g. during summer time office hours, which is healthy for soul and body and easier on the eyes than basically staring into a lamp. Also potentially a lot more energy efficient.