This also depends quite a bit on class size. If you are one of 9 profs and 36 TA's on a whole year of a 1st year intro course, you can get together and batch mark finals very effectively blind.

If you are teaching a 4th yr/masters mixed class of 11 by yourself, you pretty much get to know who is who whether you want to or not. I suppose avoiding handwriting can help if it's appropriate (e.g., won't work on a math course) but I suspect you'll know everyones style by then anyway.