I think books are awesome - especially from respected tech publishers like Pragprog. The professional editing alone is priceless.
I probably fall into @sotojuan’s group who reads a lot before getting stuck in, and although I haven’t finished learning Elixir yet, I can honestly say that going through all the books and learning material that I did when learning Ruby, was definitely not a mistake.
In fact I think my first app was actually one of my best - because all the best practises and all the knowledge was fresh in my mind 
Having said that, I am thinking of learning Elixir by getting stuck in more purely because I have to ‘unlearn’ much of what I know and I need to get into the habit of doing things differently, and I think that might be better cemented through practise. I’m still going to read lots before I get stuck in to my first app, but I am not going to make handwritten notes like I did when I was learning Ruby which would increase my learning time by 50% or more (I didn’t just take notes, but reviewed them before each reading session).
I think it’s great that some people can learn by doing or reading through code, but I’ve also seen downsides to that - sometimes an explanatory sentence or two can shed so much more light.
