I'm recording a guy now (guitar & vox) who is new to using a click...
One of his songs sounded really interesting with all the breaks, tempo and time signature changes.
Since he planned on bringing in other players for this particular song, I asked him if we could sit down and try and map out all the changes...
He looked at me sorta funny and said he didn't realize there WERE any tempo or time sig changes
When I played back his take and had him try to count it out (or when we tried to do just vocals to the guitar), he couldn't do it, although when he played and sang it, it was pretty constant each time.
I then had him 'sing' the gist of the guitar rhythm and clap his hands to what he felt the meter is as I tapped the beat into a metronome. Once he did that, we found that he felt the song at a solid 110 bpm.
I sent him home with the metronome for a week and we just redid the scratch track this weekend... The song TOTALLY gels now and all the cool little breaks and kicks he has in it really shine through.
He says he thought it sounded like that while he was playing the first time, but listening back showed him what was really happening.
The guy has pretty good meter and if the recording was just going to be him, the song probably could have stood on it's own, but now he wants to track every song on the CD to a click.