Should He Be Allowed to DriveHere?

Looking at a blog post by one Jacek "Edward" Rutkowski ( see http://ejr44.blogspot.com/2008/05/i-am-deep-in-england-now.html), I wonder not at how we allow so many foreigners into the country (that's cool), but why we allow them to drive if they haven't shown any competence. Here's what this gentleman has to say about driving in the UK;

"driving in UK is a bit strange: the priority has always the one coming from the left, not right like on the continent but what if you try to enter round-about? Then people on the round-about have always higher priority than you who is entering round-about even though technically people on the round-about are on the left side, or how it is? I must learn it some time..."

Yes, maybe you should, like, y'know, learn it before you even start to drive around here and kill someone?

Does this worry you? How do you feel about sharing the road with people who don't know if they've quite understood how the whole 'road thing' works?