About those typos:
IF you can be honest to yourself, I advice you the wonderful Userscript Double Check. One of it’s features is, that you can retype an answer by pressing BACKSPACE. I have many typos in the readings, but if I really know the reading, I just retype it.
[On the other hand: if I got an answer right, but was not shure about it, than i change it to “wrong answer”, so that i can repeat it]
~T 