Uh, no. [edit: It is not only compiler/tests.]
I also have half a dozen tabs of shell, where I also keep documentation (perldoc, pydoc, etc). (Real Emacs users use emacs buffers for all their shell needs and documentation. I'm a wimp.)
>>comparing lines of code on the screen is meaningless
I have used IDEs (not exactly lately) and have seen people use them quite a bit.
Personally, I don't make non-intuitive claims, and argue that others just don't know what they talk about, without good references.
>>presented differently, and the flow is different,
Obviously the work model is different. But...
You are arguing that all the screen area left to buttons etc is paid for by the IDE's popup functionality.
Screen estate has simple and obvious advantages, since when I write the code, I can see the documentation and/or the functions it calls at the same time.
You need references for your claim.
That said, with a language which gives Cobol fingers (Java, etc) and/or use half a sentence to write a library call, I do see a case for an IDE.
With an IDE, all of that is in the same window, but in popups and overlays. It's presented differently, and the flow is different, so comparing lines of code on the screen is meaningless, it just shows that you haven't really gotten far enough into it that you understand how it is different.