In article , Larry Dighera
wrote:

Are you relating a firsthand experience? Or have you got a cite?

I have done rolls (aileron and snap), spins, hammerheads, loops.

Try it yourself. Suspend a wet sponge attached to a string from the top
of your cockpit. Perform a series of rapid aileron rolls.
Which way does the sponge move?
Does it stay in one place?
Repeat while performing a multiturn upright spin, adding power once the
spin has developed.
Repeat while performing a multiturn inverted spin, again adding power
once the spin has developed.