As a student, I have been involved in what seems like an infinite number of workshops--both fiction and poetry. In these workshops, it seems like the question of genre always came up. "Here is how poetry is different than a short story, which is different than a novel" type of conversations. I've struggled with professors and other students over the question of genre and whether or not one author can master all of them.
The original conflict came up in a playwright class where the textbook itself said that writers could not mix genres successfully. Another professor compared the genres to sports (and I'm paraphrasing here): Poetry is like ballet and Novels are like football--one person can have some ability in both but will only master one.
That is, of course, bullshit.
The genres aren't like different sports (and I can't believe I'm using a sports analogy here), they are all like swimming. In swimming you have four main competitive strokes: freestyle, backstroke, breaststroke, and butterfly. Each may look different, requiring different muscles, and then the different events require different distances. But the basics of swimming are universal. You will never qualify for the Olympics in any of these events if you don't know the basics of streamlining, buoyancy--and if you can't move a lot of fricking water.
Writing is like that. Sure, you may have to use dialogue tags in fiction and name-colon in drama to indicate who is speaking, but if you have command of the language, that's no big deal. It's about flexing different muscles, and if you're in good shape and train then switching off is no big deal. Yes, you will probably determine that you just want to write poetry. Fine. Novels? Go for it.
But if anyone steps back and tells you that writing in different genres can't be done (and those of you in grad programs are probably under the most threat, sadly enough) tell them Shakespeare wrote poems and plays, he's legendary for both. Hemingway? Short stories and novels--equally brilliant. Oscar Wilde? Plays, poems, and one spectacular novel. Percy Bysshe Shelley? Brilliant essayist and poet.
But...but...but...they're geniuses you say.
Which came first? The genius...or the practice/work/training/immersion in language by using the different genres?