Reaching for Esc seemed natural after I played 0.31.25 for a while. But my RAM caught fire (don't blame the game) and I had to use a 500mhz Windows XP box with 96M of ram for a week or two which I was sure I couldn't play DF on but actually it ran at about the speed it does with 100 dwarves on my real box, when I had 7, in other words, it would be playable at first at least. But I couldn't play 0.31.25 because I didn't have SP2 or greater (I don't think I had SP1) so I played 40d. In 40d, the spacebar closes windows, instead of Esc! I got used to this fast and when I got more RAM for my real PC and could play 0.31.25 again, I missed it and didn't want to hit Esc.
So I bound the Exit Screen or whatever it's called, key to Space and deleted to binding to Esc. This gave me two problems:
a) Queuing a job at the manager, hitting 'space' between words exited the screen. Solution: Hitting shift-space still enters a space and doesn't trigger the binding. It's only a little annoying going "wooden [shift-space] chair" but who cares really. Even if you could only enter one word you could use the arrow keys to choose the one you meant but hitting shift-space instead obviates the issue
b) In squad view, 'space' is used to pause and unpause the game like when you're in no view. With Space bound to exit screen/close window, space can only be used to exit the squad screen, but then you can pause or unpause by hitting space again, and just return to the squad screen by hitting 's' again. Unless you have some real need to quickly pause/unpause with the squad dialog -open- ...
I recommend changing your keybinding to close windows or exit screens from Esc to Space for more streamlined gameplay
From the brain of flamoot.