[quote name='swee'pea99']Do they? They must be imbeciles.[/QUOTE]
If you look at Sheldon's article on chains, you'll see he respects this opinion but doesn't always agree with it.
"One of the great controversies of chain maintenance is whether you should oil a chain or not. The downside of oiling a chain is that the oil may carry grit into the interior of the chain, and that this grit-mixed-with-oil will act as grinding compound, causing accelerated wear. Many experts whose judgement I highly respect hold this opinion, but I do not believe that this is always the case. I have no doubt that this "grinding-compound" effect can occur, but the severity of the risk depends upon the sort of dust/soil prevalent in a given area, and, particularly, the oiling technique used."
Also, I know that on some farm machinery such as potato or combine harvesters, you have huge chains, maybe 2" wide and 10 or 20 feet long which can cost hundreds to replace and work in dirty, dusty enviroments transmitting huge torque and many mechanics insist that oiling them accelerates wear by attracting dirt. From my own observations of this type of chain, I have sympathy with that opinion.