  We investigate the spin dynamics of the square-lattice spin-1/2 Heisenberg
antiferromagnet by means of an improved mean field Schwinger boson calculation.
By identifying both, the long range N\'eel and the RVB-like components of the
ground state, we propose an educated guess for the mean field triplet
excitation consisting on a linear combination of local and bond spin flips to
compute the dynamical structure factor. Our main result is that when this
triplet excitation is optimized in such a way that the corresponding sum rule
is fulfilled, we recover the low and high energy spectral weight features of
the experimental spectrum. In particular, the anomalous spectral weight
depletion at $(\pi,0)$ found in recent inelastic neutron scattering experiments
can be attributed to the interference of the triplet bond excitations of the
RVB component of the ground state. We conclude that the Schwinger boson theory
seems to be a good candidate to adequately interpret the dynamic properties of
the square-lattice Heisenberg antiferromagnet.
