This article intends to fathom a development by M. Tailherer which introduces a second gravitational equation devised to complete General Relativity (TGR), based on the ansatz of equating the curvature tensor opportunely contracted to the 4-vorticity by a new constant S as measure of the intrinsic inertia of the curved Space-Time. After justifying the need to deal with the 2nd fundamental tensor in Relativity in discussing the dynamics of Space-Time structure, it has been shown how the model exhibits unforeseen analogies with the electromagnetic theory. As direct continuation of the analysis of the gravitational wave propagation in free space, it has been seen that on asymptotic conditions the polarization state can be retrieved as mixture of two independent modes likewise TGR as from harmonic constraints on the homogeneous solution of wave equation. Actually, in this gravitational framework, at least for one polarization state, transverse waves propagate causing equal in-phase deformation displacement, not counter-phase as expected in gravitational interferometry experiments at present status. Computation of gravitational power losses for the keplerian system B 1913+16 in the solution by approximations of the inhomogeneous problem has been carried out to the 1st order, which has allowed the assessment of a new universal gravitational constant for the first time ever.

General Relativity, 2^nd fundamental tensor, gravitational waves, Tensorial Curl, 4-vorticity