A family of Microsoft word processing software products for creating web, email, and print documents.
I've had a similar problem in Excel for the iPad fields. It happens in a fairly large, multi-page worksheet I use in fields I've created by merging several cells. I seem to be able to type data into the fields initially with no issues, but at some point (and I don't know what "triggers" this behavior), each time I hit a key it displays very slowly onscreen, and in duplicates (for example, when typing "Excel," I get EExxcceell). Each letter (or duplicate) takes at least a second or so to appear. If you hit the "Delete" key to erase the typing, it, too, erases two characters for each single push of the key. So, there's no way to correct the doubling of the characters. I've worked with this same worksheet hundreds of times in Excel for Mac 2011 and never had any issues.
I've tried a few of the same solutions as veegeedubya, but once the field starts responding slowly and with duplicates, I can't seem to get it to respond normally to keystrokes. So far, I haven't seen this behavior in Word for the iPad, but I don't use Word nearly as much as Excel for the iPad, and only have one or two Word documents that I'd routinely be using that are longer than one page and have imbedded tables that I'd be typing in.
When the slow typing begins, it essentially makes it impossible to enter any further data into the misbehaving fields. I create a duplicate of the problematic worksheet to enter health history data for EVERY ONE of my clients, so when these fields go sour on me, it creates a big, recurring problem! Fixing this issue would be much appreciated!