It is tempting to open every view we are working on in a separate tab, and this is often perfectly plausible. But, especially during the design phase, when we are coordinating any number of views and the subclasses they represent, the luxury of unlimited tabs starts to become as much of a burden as the problem it is meant to solve.
Note
A large part of getting around this problem is getting used to navigating quickly between the various panes and tabs that we have open, and using some of the navigation features to make such a plethora of open tabs unnecessary in the first place. I find that, with fewer other tabs open, I am more inclined to open storyboards in several tabs at once, each showing a different part of a storyboard (or different storyboards, which we'll see later), saving me a lot of scrolling and zooming.