Similarly I could live happily ever after with Photoshop 7.x or CS1 if they took full advantage of modern operating systems and hardware.
And I still haven't seen an increase in productivity. In fact, migration from Equation Editor 3.0 was really painful. I could type math equations blindfolded, I know Ctrl-R for a square root, Ctrl-F for fractions, Ctrl-K A for a right arrow and Ctrl-K I for the infinity. Now I have to use their "new" equation editor with unpredictable behaviour. No hot keys, or useless hotkeys that you basically have to type the entire command to do something you were doing with just two keys. Sometimes the correct maths won't even render unless I press the spacebar a couple of times! It has been a pain in the ass. It took me about 3x keystrokes and 1.5x time to do the same thing that I was doing with the old editors.