Click on the banner to login, the page will change to a login form with an [X] close button; click that to cancel and you'll be returned to the content to scroll a couple more replies until it tries again and you get bored.
Firefox in a private browser window seems to get past the registration popup for me. You have to close and reload the private window periodically because it somehow starts to fingerprint you as a user and starts showing the popup after some time.
If there's a way to configure a specific site to never ever store any cookies or send them under any circumstance that might be the next thing to try. Make twitter think you're friggin curl. Unbelievable we have to do this nonsense just to read the site.
Not gonna happen.