Where vim shines is with editing existing files. Sure, maybe your IDE has a great plugin (or great built-in support) for the specific language you're using in the project. But vim is excellent for editing any text file, no matter what language (or indeed no language at all), and its keys are always the same. If you become a vim master, you don't need language-specific support to be productive. Additionally, all of your knowledge of vim editing commands is transferrable to any kind of file you want to edit. Language-specific plugins, on the other hand, vary widely in capability, hotkey setup, and completeness.
So if all you do all day is work exclusively within a single language and you have your IDE perfectly set up for it, learning vim is going to feel like a waste of time. If, on the other hand, you find yourself extremely unproductive whenever you move to edit other kinds of files (and you need to do this a lot), then vim may be a worthwhile investment of your time.
This whole story gives me "hacker in movies" vibes. Programming isn't about artfully manipulating input devices while watching characters scroll fancifully across the screen.
It's about understanding a problem in depth, and considering possible implementations/problems/edge cases.
If you spend more time typing than thinking - I will unequivocally call you a bad developer (or a developer who's job is ripe for automation...).
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Now - no knock on Vim. I much prefer it to nano, and if you enjoy using it, more power to ya. I do agree there's a certain sense of "playing a musical instrument" feeling to it.
But playing music and composing music are NOT the same. In the same way that entering text and programming are NOT the same.
I compose because improvising on a single instrument is not enough for me. But it really is like improvising with edits, and being a good improviser will improve your compositions just as your compositions will improve your improvisations. And ultimately, you are doing these things because you love to play and hear music.
The appeal of vim is that it encapsulates programmatic thinking into the act of editing. With each edit, you are making a little program: "select these words with these conditions but not those other conditions, and then, for the first (expression x/y) of them, transform them thusly. Then, select the parent containers, and pipe each one to this file-descriptor to be processed externally."
But you can do this with a few keystrokes, you just have to think ahead a little. That is, it makes the act of programming and entering/editing text one and the same activity, allowing you to do little programmatic improvisations.
I switched from music to code when I realized I got more enjoyment out of code than music. That is, I echo your statements "if you enjoy using it, more power to ya" and "playing music and composing are NOT the same," but also: sometimes playing music and composing are the same, and sometimes the only reason you are composing (or playing music) at all is because it feels so wonderful to do both at the same time.
To study a code, it is best to copy it, run it, and keep adding assertions, comments, and logging infrastructure. Besides helping you to understand what the code does, all these changes are useful for other people who may need to understand the code in the future.
I don't often use a debugger, but they have proven to be useful in a lot of cases.
I do think the write/debug/edit cycle is a very, very slow way to program, and I have to admit I'm suspicious when somebody tells me they spend 90% their time in the debugger (but a lot of this is dependent on type of work).
And sometimes running a single test takes like 7 minutes so I have to reduce the times I run it to save time which is why I tend to fix code in an interactive REPL in the debugger.
The debugger may help you understand, at some moment in time, what an unclear piece of code does. When you revisit this piece of code later, or another person finds it, your first experience with the debugger is not remembered, thus lost. This is what I meant. On the contrary, if you clarify the code and make it easier to instrumentate (by adding assertions, tests, comments, logging, etc.), it helps you right now, you in the future, and everybody else at any time. Furthermore, as a result of these efforts you will create a code that is clearer and nobody will ever need to debug to understand what it does.
The only case where debugging makes sense to me is for cases that are difficult to add instrumentation to, like assembly programming, where it will be somewhat inevitable that you need to step through the instructions to see what's going on.
To me - A debugger is the instrumentation you're talking about, but created by the language/runtime developers instead of having to be remade by you, poorly, for each new project.
A good watch statement is a hell of a lot more useful than an assert - even though they both try to do the same thing.
Not even touching the places where a debugger solves a problem you simply can't touch with instrumentation after the fact (crash dumps immediately come to mind...).
And neither of them are (in any sense) a replacement for writing a test after you solve the problem, or adding comments so the next developer has context on the why of that piece of code.
I've had a fair share of using debuggers in my life, and I ended with my anti-debugging stance as a matter of fatigue, and a sense of time lost. I know what debuggers are capable of, especially regarding data visualization. But for your example of the variable watch, what are you going to watch, precisely? That the value of a variable is always positive? That it increases one by one? All these things are better served by assertions. What kind of information can be inferred by just looking at the evolution of values of a variable that is not easily formalized as an assert or a simple in-code test?
Basically - the debugger is not a tool I use if the issue is clear and reproducible.
Those are also issues where it can be hard to write a correct test up front. Typically - tests are passing already, but we're seeing intermittant problems somewhere. Once we understand the interaction and the root of the problem, it's much easier to put a test in place.
> by adding [...] comments, [...] etc
If you need a debugger, those are not there or not good enough, and you can only meaningfully add them after you understand what's happening.
(EDIT: there is also a wide variety in what people count as a "debugger" further muddying the debate)
I feel like the approach you are taking is impossible with the I inherent complexity of the systems I work with and for me the only chance is to follow a trail of a data point through the system like in Hansel and Gretel and see what effects it has on certain objects in a debugger.
I don’t use the debugger to understand code, I use it to find out why my tests are failing, where in the system the faulty data point comes from and if the values in each step behave in a way that is acceptable.
The second big use case for me is exploring in the debugger REPL what would happen if I change value x to y or test lines of code before I put them in the unit test, because I can only run the test a limited number of times per day since it takes like 5 minutes to boot up. I have to be very careful not to waste computer cycles.
Same with touch typing: you don't need the speed, you need to eliminate the distraction of looking for a key.
Even when you're debugging/reading code, you're still making small changes: adding a print here, removing an argument there. I read somewhere that the main insight behind creating vim was that you spend more time moving your cursor and parts of code around than you spend writing new code. So that's what it optimises for.
Whether that structural mindset helps with programming.... Dunno.