Oh, and also... if you're going to be claiming to be an English lecturer and complaining about illiteracy, you should probably master the rules of apostrophe placement first.
2) I quit to write software.
3) I would have been overjoyed had my students made the kind of grammar mistake (student's) I made in my off the cuff remark. In fact, my experience doing this has made me incredibly forgiving for this kind of thing, I guess in my own writing as well as that of others. Basically, if the meaning is clear and obvious I don't really consider it a mistake, just being a pedantic snob. The problem you get with people who really don't know how to write is the meaning isn't clear, I mean really not clear. You get, like, word salad, metaphors so brutally mixed that who knows what point was trying to be made, a level of incoherence that truly impedes what is trying to be communicated -- it can range from severe annoyance to total incomprehension. Grammar is for pedeants, get your point across and I'm your friend. Unfortunately many people can't.