If you maintain your QWERTY muscle memory, you can use it as a fallback in foreign environments, but figuring out how to smoothly setup RC files on any target is probably the ideal: https://serverfault.com/questions/400522/how-to-use-a-custom...
Personally. I gave up on Dvorak in part due to this friction when I started introducing more and more tools like Vimperator (Firefox plugin, superseded by Tridactyl) into my workflow. The flexibility of switching on a vim mode anywhere and having it be 95% what I want is very high. The other factor was I still did a lot of same-machine peering then, which it added a lot of friction to. I do know highly capable engineers who go fully down the typing-ergonomics rabbit hole and stay there, but it does consume a fair amount of one's yak-shaving budget.