hsm wrote:

Can I descent below minimums on an intermediate stepdown segment of an
IFR approach if I have the runway enviroment in sight?
On a very steep approach such as the backcourse loc-A to Santa
Maria,CA, I would like to start descending below 1700 feet prior to
reaching PATER, in order to facilitate a more comfortable decent in
VMC. Legal or do I first need a visual approach clearance?

Having the runway environment is sight is one of two requirements. The
other is being in a position to make a normal descent for a normal
landing. That is somewhat your call depending upon the airplane. But,
you would be suggesting a shallow approach, which is far harder to justify
than a steep approach. The reason the stepdown is there is to keep you
from hitting the hills southeast of the airport.

Personally, I would never consider busting PATER if IFR. I would dump it
over at PATER to pick up the VGSIs.