I cannot do any serious coding on a laptop, it's just too small. It's fine if I am traveling and have to debug something but otherwise no way, I've always needed large screens to get things done.

Some of my coworkers code in 80x40 windows and are totally fine with a single 25" 1080p screen, I have no idea how they manage honestly: I've run dual monitors since forever (running two physical video cards, before dualhead was available) and lately I find myself more productive on 3 screens at home rather than 2 at work.

For me it depends on what you're doing. If you are looking at a spec, it's annoying having to alt-tab all the time. Before I had dual monitors, I even resorted to -gasp- printing the spec so I could look at it while coding.

Nope not at all, in some cases I would say it's better. I use multiple monitors but prefer each monitor in full-screen mode. That allows me to use tmux on my main monitor and slack or a browser on another. When I'm writing code on my laptop alone I just have one open at a time, which in some ways is more immersive and allows me to focus on one thing. It's usually at home alone with no other distractions so that is also a factor.

>> Is your workflow severely impaired when on a laptop alone?

I find that with a MacBook Retina I can turn the scaling up and use an effectively higher resolution for a short amount of time to get a little more productivity.

Previously, I had an 11" MacBook Air (1366x768) and was basically unable to accomplish any development with only 768 vertical pixels.

Not severely but you do feel less effective.

No, I have my preferable setup for all screen sizes. At home, I have 28" 4k, my laptop is 13", and more than once I had to edit some config files or urgently patch something while not having my laptop, with iPhone and Prompt2 SSH client for iOS :)