by GreenLake » Sun Jun 26, 2016 10:48 pm
Welcome to the forum, Jeremy.
This could be an attempt to rig center-boom sheeting without a fiddle block.
Normally, you'd have a fiddle block (two stacked blocks) tied to the boom and another fiddle block (with a becket) fixed to the swivel. Each has an inner (smaller) and outer (larger) block.
You'd tie the sheet to the becket, run it up over the inner block, down around the inner block, up again over the outer block, down around the outer block and out to the cleat.
However, instead of a fiddle block, you can use tow blocks placed next to each other. It's a little less elegant, but works just the same. (Instead of "inner" and "outer", you get a "fore" and "aft"). In some cases, instead of a becket, there's a separate eye (on the CB) to which the mainsheet would be tied.
Now, I haven't seen this arrangement on a DS, but I have sailed on much larger boats where this is done to distribute the load on the boom (by separating the attachment points of the two blocks).
See, whether this might fit the arrangement you find on your boat.
~ green ~ lake ~ ~