Interestingly I've been using a 12" laptop as my daily driver with a crappy chair, desk and earbuds and no monitor for over two years and I've had no cardiovascular problems so far. Stressed people are quick to blame their environment (tools and whatnot) but fail to take a hard look at themselves.
Genes and your body's physical characteristics have a lot to do with it. I have a slipped disk in my neck from bad posture related to using missized chairs and desks while looking down at a 12" laptop for years and I'm not even 30 yet.
The combination of slouching your shoulders forward to keep your hands together and face-down for typing on a small keyboard, and looking down exacerbate such problems, faster for some than others—unless you happen have the build of a horse jockey.
Same here, except it's an 11" MacBook air! And I'm old enough to remember Clinton's presidency well.
I think some of us are lucky to have a flexibility gene activated. I have a 24" display I sometimes plug it into, but I've been working off this setup for a few months and it's fine.
I'm merely asking because the things I could get away in my 20's and things I can get away with in my 40's appear to be wildly different, and I don't seem to be an outlier in this respect :)
(mind you, for me second monitor is about sanity/efficiency, not ergonomics; but a well adjusted chair, keyboard and mouse make a stunning difference to my fingers & wrists these days)
