In most of cases the analogy of water hammer efect and effect of an electron in a solid is not valid. Most of time the average speed of electron in a solid is omparable to mm/s or cm/s. At a speed of that range the effect of termal motion of electrons is the dominant one, and the current flow is just a drift of electrons that flow chaoticaly inside of metal.
But (there is allways a but in some explaination), in cases of extremely fast switching devices, as it is case with the modern semiconductors in a computer parts or high current high energy switching devices, the effects are drastic. In very fast switching transistors, the leads at the source drain and gate of the transistors are verry small (because of minimization of parasitic capacitance and so on...). A frend of mine is in a field of solid state physics, and I have seen the SEM images of the gates. Even at so low voltages (2.5V - 3.3V) because of the fast switching rate and als large electric fields, the electrons are accelerated to a very large energies comparable with approx 257K [room temperature]. If we consider that the voltage diference between the source and drain is 2.5V and the method of producing such transistors is to implant several atoms as a gate, it is easy to imagine that on such small distances electron woud have only several colision in the path -> energy of an electron is comparable with 1eV => 11500 K. So single electrons have a large energies and they could make a verry large impact on the electrode.
On the other hand, in the case of gas discharge, the mean average energy of the electron is very large. For a normal plasma discharge temperatures, also the electron energies are comparable with 1eV or in case of some more hotter plasmas it coud be realy experimentaly achieved even several dozens, and in few places on earth several hundreds of eV. I hope that if You have finishe anny course of gas discharge physics or electronics, You coud rememger the effect of sputtering of the cathode. It is related to the high electron energies. As a most extreme discharge device, that is used as a extremley fast high voltage switch, lets imagine that we have to swith the capacitor of 1uF on 10kV => 10^-2 Coulombs = 10mC, and a pseudospark is designed to have the distance between the main electrodes much smaller than the free path of an electron in a buffer gas. It means that, in average, every electron that flows thru that device poses the impact energy insignificantly smaller than the charge of electron multiplied by the voltage on electrodes. That means thet first group of electron have the enrgy of 10keV = 10000eV, while the las ones have couple tens of electron volts at which the process stops.
So there exist thje efect of "electron hammer" but not in normal conductors at normal conditions (even several kA).
Sincerely Your
Nenad Sakan