Fred, yes the Onkyo test is interesting, and I'm quite familiar with it and others there, since the S&V tests are among the very few that I study carefully. And it is indeed necessary to study them carefully, especially following what the asterisks on the power measurements refer to, if a misunderstanding is to be avoided. The test results here
show that the limiting on power output by the protective devices during 5 and 7 channel operation was at 8 ohms, not 4 ohms. For 1 channel and 2 channel operation into 4 ohms(with the setting correctly left at the higher impedance)the 4 ohm outputs were 272 watts and 229 watts respectively. These are the numbers which should instill "confidence" in an owner of that unit.
Mr. Kumin, as he typically points out when he has no problem with real-world use with his lower sensitivity speakers, states that the multi-channel signals of that description "...essentially never occur "in nature" from music or movie soundtracks-only artificial test signals". These excellent results led to the highest grade of "10" being given for performance.
It's also interesting to note that earlier in the year the Denon 4810(about two steps higher up in their model lineup)was similarly tested and showed a fairly similar reduction in 7-channel output into 8 ohms, as shown here
. This again led to a similar comment that it was a result "which is neither uncommon nor particularly meaningful".
Lab test results have to be studied carefully to determine their applicability to home listening. If the multi-channel power reduction into 8 ohms was taken as representing a realistic scenario in actual home use, the absurd conclusion might be that neither the Denon or Onkyo was advisable for use with speakers rated at 8 ohms or less(meaning almost all available speakers).