As you've probably noticed, we stopped requiring that you sign in with TypePad before commenting. For many years now, I've heard complaints about TypePad and it definitely restricts the amount of conversation happening in the comments. So I've dropped it indefinitely until we can move the entire blog to WordPress and establish a legitimate sign-in process.
I'm trying to keep the comments as open as possible while discouraging spammers and trolls, but without moderating and approving each comment as it rolls in -- Huffington Post style. I don't think anyone wants that.
So you can still sign-in using TypePad, but you'll have to continue to enter your name/handle in the appropriate blank. Why? Because certain commenters weren't entering names with their comments. I have no idea why. If you don't want to use TypePad, don't use it. Up to you.
Ultimately, the commenting process is and always will be quirky. Have fun, but don't expect perfection.