I would say yes. A few years ago I signed up for one of the test sites as an employer and downloaded all their tests. I then solved them myself, well sorta half

I would say yes. A few years ago I signed up for one of the test sites as an employer and downloaded all their tests. I then solved them myself, well sorta half of them. It's easy to say that such tests are useless, and they probably are as a tool for judging coder skill. However when I did a few of these it did open my eyes to a few common solutions that I could apply in various places in my code. If you read through an algo book you'll probably find a few things that are a bit surprising like Kadane's algorithm, or some things that you kinda know how to do but you need the last piece of the puzzle for, eg various graph algorithms (is there a loop etc). I'd say the main benefit is that it illuminates what kinds of things you can solve and what kinds of things are tricky (eg knapsack), which is a useful intuition to have.