@kijanki and @atmasphere very knowledgable replies thank you! So if I follow, there's many 'dials' one can change to design an amplifier. Some have significance as measurements, some do not. I thought of this question when looking at power supplies that were all 5v but got more expensive as the amperage went up. Or as you say "These numbers might reflect good power supply, but have nothing to do with reality."
Or to say in another way, this measurement was into a shorted load - speaking of which I did trash one of these high average amps, and indeed, just like an arc welder it melted the circuit board! But as to if this means anything to making music fun to listen to.. I wonder, if you have a tube amp, even 3 watts should be pleasant enough to listen to, do these have other numbers like amperage and power supplies and damping and such to consider? I guess I just see certain numbers all the time but no real context as to why they are important, and why they do seem to have some percievable effect. At least on cost!