As long as hobbits have brown curly hair PJ can style it any way he wants and be in keeping with the text. I for one think Frodo's long tresses are rather a hindrance for an adventurer: hard to keep clean and styled, too easy to snag on things like trees, brush, and orc and Gollum fingers. Look at the greasy mess sported by Strider, I'd think he would want it hacked off or covered by a helmet. Oh well, its only a movie. :D
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