User blog comment:FairyRaven/Fairy Tail Chapter 300: Where the Dragon's Soul Rests, Review and Commentary/@comment-2214433-20120921120506

"Finally, we see the unknown Zeref woman writing something (horrible handwriting in my opinion makes her NOT Lucy, especially since she is an aspiring writer, and writers are supposed to have readable letters)"

She used her left hand to write that, also she had to use her mouth to open that pen. Makes you think she doesn't have her right arm, so she had to use her left one = horrible handwritting. It still doesn't rule Lucy out.