SilverFox,
Sorry to be pedantic, but I believe you trim for an Angle of Attack, not for attitude. The two are only the same if the relative air is coming from directly in front of you (which it won't be during a climb or descent).
The best illustration is to trim for straight and level at roughly cruising speed. Then, add power. The attitude will change (nose-up), but the angle of attack won't (the relative air will be coming from exactly the same place relative to the aircraft - not easy to see, though, unless you attach a streamer, or some other kind of wind-sensitive device, to the aircraft).
Not quite sure what this has to do with the original question, though.
I wonder if this thread should be moved to the Instructors forum? I don't know anyone on here except myself well enough to comment on their level of knowledge, but I suspect there are a lot of people in here who will unknowingly give bad advice. And yes, I most definitely include myself amonst them!
FFF
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