Is it possible to maximize precious screen real estate by hiding the command line until it is invoked?
No, currently you can only hide status line (the one above command line) by disabling 'laststatus'
option.
There is really no point in having the command line visible at all times other than the fact that vim and other programs already do it.
Well, this would be true if entering commands was the only purpose of that line, which is not actually the case as it also displays:
- the ruler (this can be moved to status line);
- number of selected files in Normal and Visual modes;
- current mode (e.g.
-- VISUAL --
);
- error and information messages.
So not showing it at all could make usage somewhat harder. Not showing it unless there is a message might be a better alternative, but in this case it will appear/disappear from time to time.