Originally Posted by Rowan
Pardon? I don't get this idea that ramped cogs and rings will "throw" a chain. The ramps and piins only come into play when the chain is shifted against them by a derailleur from the adjacent chainring when shifting up. They are "dormant" at all other times. If the scenario you and pyze put up is true, then chains would be thrown off cogs and rings on multi-geared bikes. Even with tension on a SS chain, they don't have any influence on a chain's path.
Oh, and Brock, maybe look at just using the freehub you've got with presumably the 16T already there, and get some extra spacers to replace the cogs you take off. That way you don't have to worry about a new hub, you can get the chainline you want with the spacers, and you might find the "magic gear" with a cog either side of the 16T.
Even with a staight chainline with perfect tension they will throw. Had it happen with my last s/s conversion enough times under different circumstances i.e. cranking hard to start, up hills, over bumps. Bought a non ramped cog and problem solved.