Ovechkin improved his defense ability wich is why is +/- was much better .
+/- in most cases is NOT overated .it tells alot about a player. for instance look at Pavel Datsyuk his +/- over the last 3 years has been really strong because of his ability to play defense , back checking ..and NO its not because Detroit is a great team , its because he's an excellent defender . he's a complete player . watch him play and you'll see what I mean
also that Ryan O'byrne example dosent happen often , it just so happen that when his team scored he stepped on the ice