well, I might be a little bit redeck, but I have done this soo many times it isn't even funny. Yes on fuel injected cars also.
I am not recommending anyone else do it, because there is a possibility of damage though.
I think that the car should stay running, in my experiences, this is sort of a redneck way to check to see if the alternater is working. ( disconnect the battery... car stays running = alt is good, car dies = alt is bad ) This may not be the case here though, so I wouldn't be worried. If the battery always stays charged, I wouldn't worry about it at all.
1982 Cutlass Supreme - mild SBC, tons of fun! The summer toy
1996 Silverado Z71 - the hauler
2002 Bonneville SLE - His / project
2003 Bonneville SSEi - Hers / never ending project black mirror