Likewise, it also wouldn't make any sense to have a single tap within a mobile browser bring up the dictionary definition of the word you tapped on. Does it save time? Sure, for one power user use case. But it pollutes your otherwise simple navigation paradigm with stuff popping up all over the place promoting text interaction. People hate stuff popping up all over the place unnecessarily. Better to build your navigation paradigm out of the way that 100% of people interact with the content; it's OK to have a few things buried one layer deeper, power users will find them anyways.
[0] I worked on these products at Amazon.