I've never been able to correctly spell every word in an essay I've ever handed in. It's not impossible to correct this but when I correct this the rest of my writing style will not change. One of the assignments in the CS track at my college is text analysis. From extremely basic identifies you can tell approximately who wrote some text. Even just by counting "a" and "an" you can discern the author.

Unfortunately some people don't seem to understand that there is a correlation between vocabulary, work flow, word choice, and the writer.