  The idea of a planetary origin for the solar cycle dates back to the
nineteenth century. Despite unsurmounted problems, it is still advocated by
some. Stefani, Giesecke, and Weier (2019) thus recently proposed a scenario
based on this idea. A key argument they put forward is evidence that the
$\sim$11 years-solar cycle is clocked. Their demonstration rests upon the
computation of a ratio proposed by Dicke (1978) applied to the solar cycle time
series of Schove (1955). I show that their demonstration is invalid, because
the assumptions used by Schove to build his time series force a clocked
behaviour. I also show that instabilities in a magnetized fluid can produce
fluctuation time series that are close to being clocked.
