If you can string two master nodes together, you can string any number together. There is a minimum of two involved.

Now that really rocks.
But why not just do multiple DarkSends? Seems redundant to me since you must always have the coin owners sign the transactions. I probably haven't thought about it enough (is 10 minutes enough? lol) but I can't see a benefit to it.
One node knows the source of coins, one knows the destination, but neither knows both.