I have a love/hate relationship with Vim due to that sort of thing. In theory I agree with you; in practice I find it very easy to mis-navigate in Vim and find myself next to the wrong equals sign, or on the wrong side of the equals sign, or what have you. And in my experience, recovering from one of those errors, as quick as it is, makes me wonder why I didn't just use the mouse (or trackball, in my case) to click next to the damn equals sign in the first place. (Keyboard jockeys -- which I'm frequently one of, to be fair -- often underestimate how fast using the mouse actually is, I suspect, because we think of it as, "Oh, I have to move my hand all the way over there and move something and then move back, that's nuts!" Again in practice, I suspect the mouse removes a great deal of the cognitive load involved in navigation, and that may balance out more often than we're inclined to give it credit for.)

Incidentally, in Sublime Text -- as well as Emacs and most Mac OS X applications, as this is a system-wide keyboard binding -- you could just hit ^K after the equals sign for "delete everything from here to the end of the line."