I've said this before here, but I feel that one of the things that really hindered my progress (back in the 1990s) was owning the Elementary Go Series and feeling that as a 10k I should be able to read through Life & Death and internalize it. It's a good reference in an encyclopedia sort of way but not a good way for a beginner to gradually increase his/her life and death skills. Like a previous commenter I really like the Level Up Life & Death series for that purpose.