Is capacitor noise due to observed step charging?
This is a comment - highly (probably) relevant.
While not directly answering the question proper the key point raised (a capacitor CANNOT step charge) must be understood. 

You can apply step CHARGING pulses to a capacitor
BUT a capacitor NEVER step charges.
Vcap CANNOT change instantaneously.
(The annoying laws of Physics include this fact in the definition of what defines a capacitor).

You can apply a constant current and have the voltage change as a linear ramp ,
or a resistively fed voltage and have it exponentially change voltage. 

Wishing to tempt Murphy,
you can apply a stiff voltage source
via a very low impedance path
and you will get a rapid transition and large currents - but the R &amp; L components of the charge path and the source and the capacitor will cause the voltage change to 'obey the laws of Physics'.




  You are not answering the question.
  This is not about how an idealised dogma of capacitors work.
  It is about how real capacitors behave. 


I AM answering the question.
A real capacitor is an ideal capacitor with added ideal series resistance, ideal lead inductance, ideal leakage resistance and more scattered idealities, in many cases probably distributed rather than lump.   

While the non-idealised-dogma of capacitors you buy "gets you through" often enough, you cannot avoid the laws of physics which control basic behaviour.
The ideal capacitor [tm] lurking in the non-idealised component CANNOT be forced to step change in voltage. It can SEEM to due to the ESR allowing you to apply V=IR, and the inductance to allow step voltage BUT NOT step current. And ... . 

Capacitor paralleling to reduce noise from step charge can be explained several ways (All models are wrong, some models are useful) including that each capacitor has ESR and ESL and a resonant frequency and transfer function, and that a step voltage is able to be modeled as an infinite series of sine waves of decreasing amplitude (F0 + 1/3 F3 + 1/5 F5 + ...) so your multiple-capacitor-formed band pass (to ground) filters provide a wider band width than a single cap.
The dogma of real life is complex.