When typing if you try to italicize a word on the fly, when you turn off the italics, and press space for the next word, it is turned back on, making the shortcut annoying to use. Typing should be fast, quick, painless, and have no issues like this. I know it's a minor UI glitch, but it ruins the point of being able to type something up quickly, and thus the point of having HTML mode on by default. You shouldn't have to go back and correct mistakes, and definitely not need to turn off again a feature that you already turned off once before.
Also when you have it 'fixed' (i.e. turned off for good), if you mistype that word, and backspace to type it again, italics is turned on AGAIN! Even though you're a full space away from the italicized word. Microsoft Word had an issue like this back in the day, and I always ran into it, since I bold and italicize on the fly.
Thanks for listening.