A couple of months ago I added this to my
(global-set-key "\M- " 'dabbrev-expand)
It binds Alt-Space to command completion/expand word. The completion has some clever heuristics to figure out the most likely word present in any buffer.
Anyway, the point here isn't the command completion itself, but the key mapping. On my Swedish keyboard, the default keystroke is something like Ctrl-x Shift-7. I used it a bit in the beginning once I learned of the feature, but not very often, mostly for very long names or difficult-to-spell words.
Alt-Space on the other hand, I hit that key combo a lot while typing.
Having it on Alt-space is the difference between a function useful in theory and something that changed the way I enter text. It's difficult to describe properly, but it's... different.
Proper Huffman coding seems important in many diverse situations, from language syntax to editor keystrokes to coding standards and procedures at work. If common things carry very little overhead, it may magnify their usefulness by orders of magnitude. They may become something different.