I had played with whoopie slings previously, and wasn't really sold on them - I loved the straightforward simplicity of my webbing and triangle buckle suspension on my Warbonnet. With the single piece of webbing for both suspension and tree hugger, all I had to do was pull out the webbing, wrap it around the tree, and clip a carabiner. But I wanted it to be lighter and less bulky, while maintaining that simplicity.
Enter the all-in-one whoopie sling/Dutch Clip suspension. Basically, this emulates the simplicity of the webbing setup, but is lighter and easier to adjust since it incorporates a whoopie sling. What I did was make a whoopie sling where the sling passed through a piece of rubber hose that was fastened in place inside one loop on the tree hugger. The other loop on the tree hugger then has a Dutch Clip on it, so I could simply pass the tree hugger around the tree, clip it in place, and pull the whoopie sling to the appropriate length. Since the whoopie sling is permanently attached to the tree hugger, there is no fussing with toggles, and it's impossible to forget your tree hugger and leave it behind.
Here's how I made it:
First, I tied an overhand on a bight into one end of a 12 foot piece of Amsteel. Then, I buried the working end inside the amsteel, like I was splicing it. This was mostly just to hide the ugly end of the cord, and also help prevent the line from pulling through. This will be the loop that gets girth hitched onto the Blackbird whipping mass. There are lots of threads describing how to replace the BB suspension, so I won't go into them.
Here's that loop, along with my highly sophisticated splicing tool
My next concern was how to pass the whoopie sling through the webbing loop on the tree hugger, without worrying about abrading the line or webbing when I adjust things. I decided to insert a piece of rubber tubing through the loop, then run the line through that tubing. I later put a few stitches in the webbing behind the tubing to hold it in place, similarly to how you fasten a Dutch Clip in place.
Now, all I had to do was run that line back to the hammock end, and do a 10" bury for a standard whoopie sling suspension, go hang it, and see if I fell on my butt
Here's the Dutch Clip in action:
And here's the whoopie sling bury:
And finally the connection point between the tubing and the tree hugger (this picture was taken with someone in the hammock):
There is some question about how durable the tubing will be, but I've used the exact same stuff in the lab while running experiments, and it was part of a pump that had rollers being driven against it by a motor for hours on end, and never had a tubing failure, so it's pretty resilient stuff. Even if the tubing were to fail, it's not structural - it's just there to reduce friction between the rope-on-webbing connection.
All in all, I vastly prefer this system to other whoopie sling setups. It's just as quick to deploy as my old webbing based system, while being both lighter and more compact. And it doesn't need a half-hitch knot to keep from slipping like my webbing did.
Edit: updated with some weight information:
suspension type: g oz
1 side webbing suspenson (no biner) 108 3.81
1 side webbing suspension (with biner) 132 4.66
1 side whoopie sling susp (no dutch clip) 58 2.05 (calculated - Dutch clips were sewn in when I decided to weigh)
1 side whoopie sling susp. (w/ dutch clip) 74 2.61
so the most fair comparison, the suspensions without biners or dutch clips, saves 1.8 oz per side, or 3.6 oz total. With the Dutch clips included, my total suspension weight is 5.2 oz. I'll take it.