I would love to see tutorial writers hire a proofreader for grammar, spelling, and punctuation! Most of the tutorials I have seen have been beautifully done, with attention paid both to writing and pictorial composition. However, I have bought a couple of tutorials that were nearly unreadable because of consistently poor grammar or punctuation (i.e. I am not talking about the occasional typo). The techniques being described and the craftspersonship shown in the pictures was undeniable. You don't have to be a good writer to be a good beadmaker or photographer; facility with language is not a measure of your worth as a human being. However, in my judgment you should show that same level of professionalism in the text when you are asking people to pay for your tutorial.
Free tutorials are a whole different area--if you are generous to give away your time and hard work, I won't complain about the language. If you are producing a professional product, though ... well, you wouldn't sell beads with cracks, or sharp ends, or lopsided balance, right? Then in a tutorial, which depends both on pictures and on words, I would expect you to take similar care when writing. If you know you tend to confuse its and it's, or their, there, and they're, or you sprinkle apostrophes around like croutons on salad, get a friend who excelled in English classes to proofread for you. It is a good idea to have someone else proofread your text, anyway. We all tend to read what we intended to write, not what we actually wrote.
End of rant
