Playing Skelton next weekend is definitely a gamble.
He's come on leaps and bounds this year, and has actually managed to get some pretty decent "big game" experience this season with two finals appearances and one test. A full test season in the Wallabies squad, including the EOYT and another Super season next year and Skelton will probably be coming into the peak of his powers at the world cup. By then he'll have developed most aspects of his game, he'll have improved his cardio and he'll have a good foundation of experience against most of the top tier teams in world rugby. By then Link will also have a better understanding of his limitations and strengths, in particular how to get the most out of him in attack and at the line-out.
At the moment, Skelton is a bit raw and so it is a bit difficult to know what we will get out of him this weekend. My observations of him during the Super season are that he's still a bit inconsistent. He generally came out and made a good impact, but there were other games when his involvement didn't seem to help. His set piece work in particular ( not just in the line-out but also his scrummaging) was sometimes poor.
If Skeleton was to play this weekend he could either win us the game, or he could be a bit of a liability. More often that not in 2014 he has proven to be the former, but against the world's best side, with a strong set piece, its possible he could be the latter.
The safer option is Horwill. He definitely wont be a liability, although he's also not likely to win you the game with a moment of magic either.
At the rate Skelton has risen to prominence over the last 12 months I have no doubt in my mind he'll be one of our best forwards in 2015, but he probably has another 12 months in his development before he is the world class lock some people are painting him as.
So he's a gamble for sure. One worth taking? perhaps. I'll leave that upto Link.