Terse is good (vs. the BOR "pithy") but I find many of my one-liners require a look into my brain if they are to be understood. If nothing else, it does give us opportunities to "further the discussion".
Yes, and the conversation is often worthwhile, even for the originator of the too short comment, it allows a golden oportunity to think through and articulate the original concept and a better chance of catching of the less obvious implications.