[jtkung]

A lot of experienced luthiers say that wood and construction do make a difference, and I don't doubt that they "hear" a difference. But it probably wasn't under strict controlled conditions (like below) -- or maybe just the very strong psychological placebo effect.

• Double-blind listening tests
  
• Pickups are identical -- which means they have to be swapped in and out
  
• Pickup location and settings have to be the same (same height from strings)
  
• Same type of strings with the same playing time (age)
  
• Electronics have to be the same (pot values, caps, etc.)
  

What it means is that it has to be properly controlled where you are ONLY changing the body wood, or neck wood, or whatever variable you are testing for. 

For example, a Les Paul doesn't sound like an ES-335, but are

• Pickups identical?
  
• Pickup locations identical?
  
• The bridge and nut identical, as well as break angle?
  
• Strings identical?
  

The answer to these is usually NO.  Also, the ES-335 is semi-hollow and thus will feedback at high volumes. This is where the resonance of the body could affect the string vibrational energy. But it is less so in the Les Paul.  And this is regardless of the body woods used!

Essentially just putting your hand on the neck and your body against the guitar body changes the resonance, but not really enough to be audible through pickups. Or even acoustically on an electric. 

In terms of whether the body really makes a large difference in electric string tone, see this test below. Debunking decades of marketing bullshit!