OT guitar backup

Is guitar backup just the slightest bit behind the beat in a dance tune 
with a fiddle lead?  Here's why I ask: A few times I've overdubbed over 
my own fiddle part with a guitar backup on a multi-track recorder.  It 
feels sort of artificial, compared with playing simultaneously with 
another live person in a jam, or when recording live with someone else. 
  My perception is that I've noticed that if the guitar isn't just 
slightly behind the fiddle, it makes the fiddle sound uncertain, or not 
swingy, or somehow out of sync.  It's all very slight, so it could just 
be my ear or sense of rhythm.  I'd be curious if anyone else has this 
same perception.

Geff