The 30" quoted by the GP was 2560x1600 pixels The TB 27" monitor has 2560x1440 pixels (10% less) That's close enough for the ballpark calculation of the GP.

The 30" quoted by the GP was 2560x1600 pixels The TB 27" monitor has 2560x1440 pixels (10% less) That's close enough for the ballpark calculation of the GP. (I'm not saying I 100% follow the GP's understanding of the numbers and systems issues, because I don't. I responded because I've seen the two-monitor, one-cable setup in practice.)