Did you stay up all night thinking this stuff up.
When the mechanical curve STARTS advanc ing at 1100 rpm,, anything below 1100rpm is
is initial timing. Cause the engine is idling below 1100rpm and is on the base of the curve.
That is the initial timing.
All you do to set the inital timing is disconnect any vacuum advance and slow the engine idle speed down
and set the "initial timing" with a timing light. The timing will not start moving till 1100+ rpm.
From that point you can now set the idle speed to what ever makes you happy.
But it will be less than 1100 rpm anyways.
Your only purpose here is to make up and argue terms, not help the poster get his distributor set up correctly.