[s17tnet]

The productivity after the second screen decrease because the software sucks at support those configurations.

With specialized software ( multi track AV) and/or ad hoc setup ( e.g. deeply tuned Linux) the more the screens you throw at it, the better.

[graphe]

Virtually perhaps, physically there's a limit. https://www.viewsonic.com/library/business/monitor-ergonomic... ViewSonic doesn't account for more than one monitor for an ergonomic workstation, and I've never seen it done well myself.

[kergonath]

There’s a paragraph under the title “Account for Dual or Single Monitor Arrangements” on that web page. They just say that you have to be particularly mindful of ergonomics if you have more than one. How is that not accounting for more than one?