Personal theory of mine is that it's just a sample size variation. It's not the stat that's flawed but the evaluation of defense itself. Guys may not get hit balls to them in one season, and end up with a +2.5, but then next season they do and get +5.5, despite the ability being pretty similar, but this is just speculation with no evidence.
Basically, guys are capable of huge, isolated seasons, but it evens out over the course of a career. So Goins has had a huge 58 game sample, and that's not luck, he's a great defender. It's just that he's probably not an all time great which means he'll regress to join the rest of the above average and very good pack.
It would be the 30th best mark ever career wise, above Elvis Andrus, Alexei Ramirez, Troy Tulowitzki, Jimmy Rollins, but below Brandon Phillips, Mike Moustakas, Aaron Rowand, Geoff Jenkins, etc. It's very good company.
I don't think even a full year is enough for it to stabilize. And even then, it'll always fluctuate based on whether he gets balls hit at him. Defense is weird.
Nobody stays that high. The highest among qualified 2B was Utley at 19.2 one year. A 7.5 UZR is really, really good. High above average. 33/150 is historical and I think we can agree that even if Goins' defense is great he's not an all-timer.
If you regress his defense to above average like it probably is over a large enough sample size then I'm fairly sure it's more balanced
I know your IQ matches the number in your username and all but this isn't what I was saying and also your dumn