Effect on opamp lead length for non-functional wien bridge oscillator
While this is not certain, there is a very good chance that you've been burned by resistor tolerance. 

A Wein bridge oscillator requires a gain of 3 at the resonant frequency, and for your configuration that means a 2:1 (or better) ratio between R1 and (R2 + R2a). The nominal values you've got give a gain $$G = 1+\frac{R1}{R2+R2a} = 1 + \frac{4.7}{2.3} = 3.043$$ which provides a slight gain margin over your minimum of 3. 

However, you've used 5% resistors, so the actual value of R1 could be as low as 4.465, and your R2/R2a could be as high as 2.415. This would give a gain of $$ G = 1 +\frac{4.465}{2.415} = 2.849$$ and this would explain your failure to oscillate.

Replacing your resistors with 1% units is a good idea, although it's still possible that the unit won't oscillate. If this happens, try removing R2a and see what happens. You might also measure your existing resistors and see just what values you really have (do it with the resistors disconnected from the circuit).