Originally Posted by
tetonrider
a magnet is always going to be more accurate, no?
Sure. My point about accuracy was just that any crank-based system will measure cadence more accurately than a powertap, because a powertap isn't using its accelerometer (or any other mechanism) to measure cadence, it's inferring cadence from peaks in torque. My comment was intended to mildly refute shovelhd's statement that a powertap uses its accelerometer to measure cadence if there's no cadence sensor installed.
It's all pretty pedantic.