Thank you all for your helpful words. All read and understood.
To answer John's first point very briefly, I am, of course, a very, very long way down the curve from you test pilots. I am an ATPL with a few thousand hours, of which probably 2,000 are on light twins and maybe half of those on the Aztec. I was in a University Air Squadron, where Her Maj was kind enough to show me how to do basic aerobatics 'n stuff. I have done most stuff from Tiger Moth to HS125 at one time or another. So, no, not quite an incompetent idiot, but again, no particular training or experience to equip me for this game.
Yes, I meant using the throttle to simulate engine failure.
The only times I have deliberately killed an engine in the cruise is for C of A climbs, but I have also lost an engine at cruise speed due to fuel leakage, and in both cases the effect was utterly benign, with very moderate rudder input to stop yaw. I am not quite sure whether the wing down technique, with the ball half out of the box, actually induces slip, but my understanding is that that is the minimum slip situation. Anyway that is the technique I have used.
I think that the advice of not to experiment, but to be certain what I am going to do in the event is very good, and certainly makes me very glad that I decided to air this issue here!
I have read the POH several times and cannot remember seeing a maximum bank angle, but there are various technical limitations about "utility category" and "no aerobatic manoeuvres" which might, on investigation, turn out to limit bank angle. In fact the technique I use is to sit in a stable 60deg turn and then, when the right angle is coming up for the photograph increase the bank angle momentarily to around 80deg to allow the photographer to take the picture without the wing getting in the way. There is obviously a fair amount of g involved (under the circumstances) which can be quite uncomfortable for the photographer who is twisted around at an angle and looking down through a view finder, so I try and keep the very steep part to a minimum.
I completely take the point about the critical engine. On the Aztec, the left engine is very much the critical one, not only because of all the usual aerodynamic and torque reasons, but also because it drives the only hydraulic pump. For this reason I always make these turns to the right. I assume that the same engine remains critical in a steep turn?
I really do appreciate your comments. I think that John has quite rightly put me off the idea of doing the experiment, but at the same time has given me reason to feel less uncomfortable about the exercise in general.
Incidentally, I heard this evening that, as yet another spin-off of 9/11, all orbiting is to be banned over Central London and there is to be a general minimum transit altitude of 1800'. What a bummer
Thank you all,
Timothy