It's not just the information that matters, it's the communication of the information. If your post could be understood better through some rewording and proper capitalization, then those edits should be done. Try to not take it so personally. It's not personal. Your knowledge is valuable but your grammar may not be infallible.

Besides all of that, he may just be trying to earn a badge and sees proper capitalization as an easy, legitimate edit.

It's not just the information that matters, it's the communication of the information. If your post could be understood better through some rewording and proper capitalization, then those edits should be done. Try to not take it so personally. It's not personal. Your knowledge is valuable but your grammar may not be infallible.

Besides all of that, he may just be trying to earn a badge and sees proper capitalization as an easy, legitimate edit.

EDIT

I'm also going to add that a site whose FAQ recognizes its mission as being for professionals should look as though the answers were written by professionals. Would you write a proposal to your board or your clients that used slang, used abbreviations, and didn't capitalize?