Speedskater said:First he insisted that it is questionable that the the SRM is accepted to be absolutely precise, just because its on the market for 20 years.
Absolutely not. No. The SRM is not accepted to be 'absolutely precise' by any right thinking person. It is accepted that it has a low error (particularly in the science version used in the study). This is not 'just because its on the market for 20 years', but rather because it has been validated over and over in a number of scientific studies. Powertap has also been subject to some of these studies and passed well. For Powertap there has been a question identified in the literature of small variations in very high wattage situations depending on gear selection/cross-chaining. It's very minor though, not at all like the wild fluctuations the Ergomo had in the study.
Ergomo falls down at the first hurdle.