It's a little trick that I think many will find as easy... but for others have a first time looking, may not know. For myself, the error message is not something the public audience should see. It makes the tour look bugy, even if it has loaded improperly, often times still has functionality. The end user will often never know except for that message. I too wish I could edit that message...say something like "poor internet connection, loading error" or whatever.
Re: How to remove "registered to" information from error message?
PTP 2.0 may contain an "advanced" option that allows to hide errors. But as Andrew said, if you hide errors you do not fix them. So I think that if this option is added to PTP, an annoying confirmation window asking "Are you sure to be sure ?" will be added too :-)