> Do I need to know how a gearbox works to drive stick shift?
No, but it helps. If I treat my car's powertrain as a black box then it won't be intuitive that:
* I shouldn't slip the clutch to hold my car on an incline.
* Blipping the throttle gives me smoother downshifts.
* Double clutching lets me shift from 2nd to 1st while rolling.
* I can use the engine to slow my descent on longer hills and avoid brake fade
* I should park the car in gear for safety
* etc.
Whether it's better for a given person to memorise that list of facts or to understand the concepts behind them would depend on how much they drive. As a developer I've found it helpful to gain an understanding of the tools I use daily beyond "here's the commands to copy/paste when you want to do xyz".
It may not have sounded like it but I'm actually going to agree with some of this. We might be on a different part of the gradient so to speak. Maybe you can find a good analogy but at least from my point of view the gearbox analogy is falling short now and we'd need a different one or look at git commands one by one :)
Like you say, you can just remember those things. In fact 4 out of those 6 were taught in driving school and you had to remember them. One I only learned because trucks still needed that (double clutching while shifting - not just your case, just in general) but cars didn't when I learned. I personally don't like copy and pasting commands like that but I see a lot of people doing that even for stuff that should be second nature because you need it all the time. I think - to stay in the analogy - for me this is the difference between knowing that I should engine break and how to do it when I want to slow down vs. having a piece of paper in the glove compartment that I pull out and check for what to do and how every time I approach a red light ;)
I'm also someone that likes to get an understanding of the things that I use and do every day. The thing is that there are so many things we use and do all the time that I think (almost) everyone just has to keep a certain level of abstraction away from many things, because there are just so many rabbit holes out there and it's not beneficial for most people to have explored every single rabbit hole all the way to the end (the 'gradient'). Git commit graphs are a DAG and lots of cool things can be done with DAGs, most of which I totally forgot about since I learned about and enjoyed them in university and have never needed them again at that level. It's good to know they exist and be able to dig in when needed/wanted.
You're absolutely right, there are about a million and one rabbit holes you can go down if you _really_ want to understand the tools you use but in the vast majority of those cases you're better off relying on a higher level abstraction.
The interesting part to me of your analogy is that it can demonstrate how having an understanding of what's going on under your layer of abstraction allows you to generalise.
To wring the last bit of life out of the gearbox analogy: if you tell a mechanically inclined driver that blipping the throttle will make their downshifts smoother, they'd hopefully understand how rev matching can be generalised to upshifts too. If you tell a "black box" driver then they probably wouldn't be able to do the same. Of course, the analogy falls apart a bit because understanding rev-matched upshifts isn't particularly useful :)
I've forgotten most of the "advanced" git knowledge I ever learned but I get a lot of value out of the (admittedly not very advanced) understanding that, as you said, commits are a DAG and that branches are just named pointers to nodes on the DAG. That understanding lets me generalise to, for example, backing up a branch (with git branch/tag) before doing a tricky rebase so I can restore it (with git reset --hard) if I need to undo.
I agree that exploring every rabbit hole to the end isn't beneficial - understanding the DAG is typically the only "advanced" git knowledge I need and I've only very rarely had to peel back more layers. I think this:
> It's good to know they exist and be able to dig in when needed/wanted.
is a good way of putting it. My ideal low-level understanding of most tools is knowing just enough that I know what to search for if I ever need to go deeper.
> That understanding lets me generalise to, for example, backing up a branch (with git branch/tag) before doing a tricky rebase so I can restore it (with git reset --hard) if I need to undo.
You can also do `git reflog` on branches to see what they used to point to :)
No, but it helps. If I treat my car's powertrain as a black box then it won't be intuitive that:
Whether it's better for a given person to memorise that list of facts or to understand the concepts behind them would depend on how much they drive. As a developer I've found it helpful to gain an understanding of the tools I use daily beyond "here's the commands to copy/paste when you want to do xyz".