The free productivity app WritingPad quietly and neatly eliminates the problem of stabbing the iPhone's keyboard in order to type an e-mail or note. Instead of entering letters one by one and waiting for the predictive text to kick in, you use your finger to trace a line from one letter to the next, so it will essentially looks like a squiggle on the keyboard, but it renders as a letter.
You don't have to concern yourself with avoiding letters you don't need, or with double letters like o's or n's. You don't even have to worry about manually entering a space between letters because WritingPad will do that, too. In the event your word isn't in the predictive list, it helpfully lets you add one to the library by entering it letter by letter and then pressing the Space key.
WritingPad struggles with "I'm" and makes it hard to easily access common symbols like the exclamation mark. It also won't work in landscape mode at this point. You may not use WritingPad to replace your e-mail in-box when composing e-mails, but these are minor problems when you consider you gain the convenience of being able to to mail notes to your contacts.