That is indeed, quite an interesting piece, although most of the refresh rate 'issues' seem to be due to drivers, not as much hardware limited.
Since the rig in your sig uses a dedicated GPU, I do not expect any trouble when running your monitor from it, however when you are using your laptop you might find some frame rate drops.
This is what I take from the article.
As a fellow webdesigner, I find two dedicated monitors easier to work with then multiple screens on one. This is however very personal, as several of my friends rather work the other way around.
All in all, I think it would be best to experiment a little, if possible, and find out what you like best.
Miraqbel