  The Intlerlayer Josephson coupling between the planes of Tl2Ba2CuO6 was
determined using infrared spectroscopy and magnetic flux vortex imaging. These
methods give a consistent value of $\omega_J$= 28 cm$^{-1}$ which, when
combined with the condensation energy produces a discrepancy of at least an
order of magnitude with deductions based on the interlayer tunneling model.
