Ignoring the issue of inter-char gaps
I had a command file once that would download
characters to the VT220 and then use them to
display "cute" propmts (Snoopy and the like).
One of the prompts was a sports car and, IIRC,
appeared to be wide enough to require two
characters. I don't remember a gap there so
I suspect that there is no inter-character gap
(at least in the horizontal direction).
Antonio