I ran across this while looking thru Putnam's "German Aircraft of the Second World War", JR Smith and AL Kay, '72...
"During dogfights between Fw 190s and RAF fighters it was not uncommon for the Luftwaffe aircraft to flick on their backs from a very tight turn and crash at full throttle. The cause of this disastrous behaviour was the pilot making excessive use of the electric tail-trimmer, an ingenious invention of Focke-Wulf, in an attempt to tighten an already very high 'g' turn, the aircraft eventually entering a high speed stall from which there was no recovery".
JL
Buzzard - there is a possible alternate cause. The Germans recognized the problem of high speed stall and eventually figured out one cause (could have been more) for the violent High G Stall.
They figured out that outer wing span area stalled about the same time the as the inboard 80%. The Fw 190 had a fairly unusual application of chord twist, starting at positive 2 degrees at root and ending at 0 at 81.5% of the span - then zero to tip. Most wings will twist all the way to the tip to ensure that the tip will stall last at high angles of attack.
I haven't read the report itself but familiar with the conclusions which state the outboard tip are stalled as a result of elastic deformation under load.
The mode is something I am not sure of just yet.
The aileron on the down wing is 'up' which would make the mean chord, locally in the aileron area, 'negative' in that it would be negative angle from the inboard wing.
The load due to the aileron in that outer region could be torsional (likely) or pure bending if the center of that load was on the main spar.
I suspect torsion, and further suspect that it was to twist the tip area 'up' meaning that the local Angle of Attack reached CLmax faster or at the same time as the inboard region.
The net is that I don't know for sure, but this is more plausible to me than changing horizontal stabilizer incidence to cause the subsequent stall. Changing the tail incidence to me could dangerously increase loads on the fuselage as well as create potential stability issues.
Do you have another source that I could find on the Fw 190 elevator incidence problem?