The effect of Coulomb excitation on the quasielastic cross section and analysing powers in the scattering of 170 MeV polarised ²³Na projectiles by ²⁰⁸Pb is investigated with a with a coupled-channels method. The calculation considers the coupling to the first excited (5/2⁺) state of ²³Na at 440 keV. It is shown that, while a strong departure from tidal spin conservation is predicted for the inelastic scattering, the quasielastic cross section and analysing powers agree reasonably well with tidal symmetry.