I go back and forth, quite frequently, between two monitors of vastly different sizes. Usually, I am on my laptop, hooked up to a larger monitor, viewing things on the larger monitor, but about 35-40% of the time, I'm just on my laptop. TWC handles this switching setup seamlessly.
I tried the solution you suggested, for a while, and it just didn't work at all for me. It would mean that I'd have to permanently set it for viewing on only my laptop screen, not my main screen, which is just awful. I bought this larger monitor for a reason, you know?
There were a bunch of other tweaks and hacks I tried, but I usually try to tweak one thing at a time to see its effects, and then gradually get it how I want it. After weeks of fiddling with it, I gave up trying to make a visual setup I was comfortable with, because it became clear that I'd have to full out learn CSS and make a completely new stylesheet, in order to get things I had seen implemented as default before. It frustrated me, so I'm not actually interested in TW5 anymore until for now, until there exists a pre-baked theme resembling the look and feel of TWC (with collapsible sidebars, like the easy to add plugins provide). It's cool, I'm not mad at anybody or anything; I know how hard doing all this coding is. I'm just gonna go use something I can use.
Cheers!
-Leo