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Chase: Do you mirror your displays or have separate content on each? If not mirrored, do you get the dock on both screens?

No, mirrored displays is useless really.

If you just plug in the monitor to the MBP, it will act as an extra desktop space (the MBP display won't change). There is no Menu Bar and no Dock on the external monitor... just extra screen real-estate.

After you've plugged it in, go to System Preferences -> Displays and you can align the displays so your mouse flows seamlessly from one display to the other.
 
I do this with my MacBook in clamshell mode when I'm home and unplug and use the screen while on the road...I've had no issues other than a little lag from time to time (my guess is the culprit is the 9400M GPU) that doesn't really bug me.
 
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