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Well, the title is quite self-explaining. I haven't read anything so far in Hartshorne's Algebraic Geometry, but looking at ME (and listening to what a close friend of mine told me about it) it really seems that one has to prepare to hard and painful days if interested in reading/studying it. Actually, ME has lots of questions regarding this exercise or that (not so clearly given) proof in that book, and so I wondered if it might be helpful to add a specific tag for problems related to Harthsorne's studying (just to order things a little bit more and improve searches).
What do you think about it?