OK, I am a Technical Writer with lousey spilling (LOL). I blame it on my engineering background.
I don't notice it happening, but it would be nice if prefight flaged spelling errors in the Prefilght Panel. Maybe it could have an option to check or not check spelling during preflight. Am upgrading from CS% to CS6 soon and not sure if this has changed.
You can have a preflight profile check spelling errors, Do the following: Preferences > Spelling > Enable Dynamic Spelling. Then define a new preflight profile, and under Text, select Dynamic Spelling Detects Errors.