In reply to:
3. Speaker impedance is not fixed across the spectrum (may dip from 8 ohms to 4 ohms or lower)
Rat, this is something i briefly noted earlier as a variable unaccounted.
Gena measured the individual situation with the originally described setup so the numbers apply properly in this case. When deriving 'what ifs' for other situations then the idea is expanded just as you did and obviously an argument can be made in the second instance.
In Gena's example (or rather real world situation) this newly derived situation is moot.
However, it would apply to me since i own speakers (6ohm) that do dip to 4ohm, in a large room, and as such, i need a beefier amp for the SPL i use with this specific setup.
All i use is a receiver in my 5.1 media room though. The area is small enough (and speakers less demanding, more efficient) to attain the SPL i require. I've already setup my receiver to stop its volume increase before its distortion point is hit, plus a small safety margin.
