Underblanket question

[marc]

We've just started making a couple of light KAQ underblankets for our Hennessy expeditions. Now, I see that on the group-buy Snugpak UB there are two additional shockcords in the middle of the UB. Searched the threads/photos but I can find no info on

1 if they are really necessary ( although I guess anything stopping air movement is good )

2 how they are fitted ? By which I mean are they attached to the outside shell of the UB, and thus compressing the insulation a touch, or are they fitted to the inside shell? Or are they sandwiched in the middle of of the insulation?

[wentworth]

I don't think you can go too wrong just following the instructions on the KAQ site. Patrick changed the design of the quilt after customer feedback, so it should be pretty much perfect. From the photo's I've seen, it seals better at each end than other synthetic underquilts.
I'm planning on making one up as soon as I can justify having yet another quilt...

[bikething]

The two shock cords half way along the sides are just loops formed in the middle of the two edge cords. They allow you to fine tune the fit a little (or if it's really cold you can pull the 2 sides together over you and tie them together to form a sort of pod :) )