Now it seems that no-one comments at all here (to be fair, the blog itself has been quiet), so I am planning to change thing to make it easier for visitors.
For the moment, if you wish to comment, you should be able to, simply by logging in with your Google credentials, Livejournal, OpenID or WordPress. You should just be able to do this by clicking on this link at the bottom of any article
and then clicking on the relevant symbol.
or you can register and get a username and password.
What you can’t do is use Facebook to log in with, because it looks like that no longer works.
Personally, I’d go with Google, almost everyone has a gmail account, no? But I will try to sort it out in the next week or so to make it easier for people to participate.