  The tunneling spectra of high temperature superconductors on
Bi$_2$Sr$_2$CaCu$_2$O$_{8+\delta}$ (Bi-2212) reproducibly show a high bias
structure in the form of a dip-hump at voltages higher than the gap voltage. Of
central concern is whether this feature originates from the normal state
background or is intrinsic to the superconducting mechanism. We address this
issue by generating a set of model conductance curves - a ''normal state''
conductance that takes into account effects such as the band structure and a
possible pseudogap, and a pure superconducting state conductance. When
combined, the result shows that the dip-hump feature present in the
experimental conductance curves cannot be naively attributed to a normal state
effect. In particular, strong dip features found in
superconductor-insulator-superconductor data on optimally-doped Bi-2212,
including negative dI/dV, cannot be a consequence of an extrinsic pseudogap.
However, such features can easily arise from states-conserving deviations in
the superconducting density of states, e.g., from strong-coupling effects.
