Plenty of “theorists at heart” still think it’s boring to do lots of rote drills. :-)
It’s not like doing drills really helps you develop new models/tools/concepts from first principles especially more than it helps you adapt existing models/tools/concepts to new situations.
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I think the article under discussion here misses the point in a different way. He assumes that it’s impossible to get meaningful fast feedback about various particular aspects of your work (and focusing on those deliberately) while working on “projects”. But at least in computing (and probably most fields if you look around), that’s not necessarily true.
We have tons of quality feedback available in computing, starting with tools like a REPL or a debugger which interactively show you the results of small actions, and then compilers and static analyzers and profilers and ....
Then there’s IRC and mailing lists and open source ticket trackers etc., where expert strangers will spend tons of their time helping you out for free just to pass the time. If your project happens to be something that other people are interested in and you are working in the open, there’s feedback from customers, other programmers, etc. If working in a group of mixed ability, there are the other group members or possibly a skilled mentor/tutor, and if working in a company there are coworkers.
There is oodles of open source code, documentation, free textbooks, targeted videos of people demonstrating how to use particular development tools or their general method, or showing off particular tricks, much of which is reasonably searchable and can be called up from the internet on demand when a particular problem/roadblock is stuck. You can relatively easily try to implement parts of projects yourself, then go find an example project where someone else implemented the same thing, and compare the two. Typically you can find both toy examples and production code, with their entire version history, internal project discussions, bug tracker history, ....
Arguably you could learn a whole lot by coding up 30 different examples of data structures in C, one after another, getting expert feedback after each one. And then moving on to coding solutions to 20 different dynamic programming problems. And then 10 compilers for different little languages. And then 10 different CRUD apps for made up restaur. Or whatever....
But you could also get lots of good experience by building a whole project that you personally care about from bottom to top, using it for a while and watching where the bugs come up, seeing what parts are completely wrongly architected, etc., and then trying again several times (ideally with a bit of introspection and research in between) until you have a better idea what to do.