I do actually like that they don’t resort to water analogies like a lot of electronic instruction tends to. The hydraulic analogies I think only work to a point and then become more of a hindrance to deeper understanding, so you eventually have to un-learn it to progress.
I guess there is probably an ideal middle ground where it can be presented as a “you can think of it kind of like this analogy, but then here’s the actual concept you should learn instead of learning the analogy” kind of way.
Re: analogies, having spent years answering questions on electronics.stackexchange I think the worst one is probably the electron.
At this point you'll be halfway through typing "but electrons are real, not an analogy" - but what do you think of when you think of an "electron"? If it's a ball, or even a point, then that itself is an analogy which will break down in all sorts of annoying ways. Electrons are slippery little non-localized bastards which can tunnel through solid objects. And don't get me started on holes. People like to think of electrons as "real" and holes as "not real", simply because they're defined by their absence, but in semiconductor physics they are both equally real and important.
If you use electrons, you have to face all sorts of basic problems like "why does electricity travel much faster than electrons move?" and "Why is the sign wrong on all of my calculations?" and "Which direction is current actually flowing?" These confuse people with an intermediate understanding.
It's much better to start with the field as primary. People understand gravitational fields and magnetic fields reasonably well. From these you can build an understanding in which it's the field carrying all the energy and the electrons are just along for the ride. Each carrying its own tiny electric field.
As someone who teaches electronics my experience is that analogies (including the hydraulic one) are immensely helpful to students as long as they understand them as analogies. I always tend to say, that in reality one has to look closely at transfer curves and formulae, but this would be true for actual hydraulics as well.
My goal in the use of analogies is to give them a basic "if there is more of that, there must be less of this"-kind of intuition. This is a really, really useful skill that helps you in practise, because you will automatically do a double-check if you miscalculate or if the result doesn't fit your intuition (and thus sharpening it).
After understanding the basic systemic relationships one can go and have a more accurate look, but depending on who we are talking about and what they want to achieve that might not be needed.
Many electronic calculations could also be done on a deeper physical level, which would be more accurate, but also much more expensive to calculate. This is not practical for the typical electrical engineer, which is why they go for the simplified calculations.
Similarily there are amateur tinkerers which will be able to do most of what they want by relying mostly on analogies and that is okay as well. The math is there if you wanna go deeper as an amateur, just as physics is there if you wanna go even deeper as an electrical engineer.
That being said the analogy also serves a purpose for the electrical engineer. Everything is quicker if you intuitively know that voltage has to rise at point x and less current goes through point y etc. Sometimes you don't even need to know how much
For me it made sense when thinking about DC. It misses a couple important paradigm shifts for AC though, like resistors sometimes being used to set the ratio of voltage to current, rather than resisting anything. Gets even trickier at higher frequencies, since you have to start imagining the pipes all being made from soft material or something to model the capacitance and inductance of the wires. But how do you model the EM fields being at right angles to eachother? Also I just can't make the cross coupling of wires work in the hydraulic version. Hydraulics are contained to their pipes, their is no field surrounding them. Ditto with explaining something like a transformer. Not to mention the importance, in practice, of the right hand rule, for which I have found no good hydraulic explanation.
If you have hydraulic explanations for these, please do share.
Yeah, I work in RF and am glad I never even tried to think about any of it that way. I didn’t think about that difference - perhaps that’s why I feel so strongly about it!
I guess there is probably an ideal middle ground where it can be presented as a “you can think of it kind of like this analogy, but then here’s the actual concept you should learn instead of learning the analogy” kind of way.