It will be very convenient. 
Not that I know of, you’d need to dig into the gettext documentation to find out if that’s possible at runtime.
Bad news…I’ve checked the documentation and look into its source code. There is NO way to clear cache. I hope there is an alternative to gettext somewhere for testing. :
Why not? This is working on 85% strings right now.
Oh, I mean reloading the strings for the same language.