  These proceedings contain the 'physical' derivation of the Wandzura-Wilczek
relations for the spin-dependent structure function g2 (amounting to keeping
the intrinsic transverse momentum of quarks, and neglecting the physical
transverse components of the gluon fields), recently generalized for the case
of non-forward processes (hep-ph/0102209). The simple numerical model for the
twist-3 contribution to g2 was also suggested.
