I recently received the following e-mail:
Hi.
I have just been reading through your blog - I installed your excellent xinha here xpi earlier - great job indeed. You have some interesting content on your blog. My mother was an English teacher and I have an annoying habit of feeling I have to point out mistakes. :) So here I go.

You keep using the word 'their' instead of 'there'.
Their = belongs to them
There = indicates position.

Also, where words are basically made up, such as the verb to zombify, they should be used consistently with words of a similar nature that do exist. For example; to electrify. Something electrifies, not electrifys. Therefore, you should write zombifies, not zombifys. Other than that, keep up the good work. All the best,

My response was:
Thank you for your comments. Yes, I do know the difference between their, there, and even they're. I also know the difference between its and it's, effect and affect. I even know that irregardless is not a word. I do, however, have trouble with comma use. In any event if I seriously took the time to grammar check every post I would never get anything done. As it is I rely very heavily on the spell check to catch many mistakes and still many posts take upwards of an hour. Surprisingly, I work as an engineer and my grammar is considerably better then many of my co-workers.

I thank you but if knowing is half the battle, then I'm satisfied with a tie.

With more practice perhaps my writing speed will improve and then I can focus more on the details. Untell then please accept my apologies.

Reminds me of an eirlier e-mail that was not so friendly and seamed almost hostile.

Credibility comes from attention to detail.  Try spelling "copying" correctly on your page.

At least if you are going to criticize my grammar please be polite!