On 01/10/2016 10:27 AM, Alan Mackenzie wrote:
> This might be OK if the only reason you every use M-x is to execute a
> command.  But it's not.  People (in particular, me) use it to discover
> Emacs, to find the exact name of a command which has only vaguely
> embedded itself in the memory, to get this name into the kill ring to be
> yanked into another source file or into documentation, and so on.  Try
> M-x <tab> <prior> sometime, and explore the wealth of Emacs commands.
> :-)

Funny, that doesn't work at all for me. In particular because M-x already heavily "censors" its results by only proposing interactive candidates. So I use C-h f instead. And even then that doesn't work great, because often it's in a package that isn't loaded (see my recent thread about pulse.el :/)
When I'm specifically looking for a command, I use M-x; and it works well right after starting Emacs (I get only autoloaded commands plus a few already loaded things). After a few hours, the M-x list becomes huge and cluttered.