You are mostly correct. According to FAA-H-8083-3, "Airplane Flying
Handbook," pages 5-12 through 5-13 under the heading of "Sping Procedures":

"The entry phase [of a spin] is where the pilot provides the necessary
elements for a spin, either accidentally or intentionally."

"The incipient phase [of a spin] is from the time the airplane stalls
and rotation starts until the spin has fully developed."

"The developed phase [of a spin] occurs when the airplane's angular
rotation rate, airspeed, and vertical speed are stabilized while in a
flightpath that is nearly vertical."

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Now, You are correct in that dropping a wing is not necessarily a spin,
but it CAN be considered the entry phase of a spin. We were in an
incipient spin based in the sight picture having gone way screwy on me.
My instructor was demonstrating how uncoodinated flight during a
power-on stall can cause the plane to snap and very quickly develop into
a spin. I don't yet know how far the spin developed, but I would think
it was between 1/4-1/2 turn.

Personally, I would feel much more comfortable knowing I can both
recognize and recover from a stall (at any point in the stall process)
and recognize and recover from a spin (at any phase of a spin). If that
means I spend extra time on stalls and spins, fine by me! You only get
to screw up once if you don't recover.

Cheers!
Chris


Ron Natalie wrote:
Dropping a wing is not a spin, just a sloppy stall. The time is better
spent on nailing stalls than spinning the airplane.