The "standard" dropper loop, with the twist-and-through, is appallingly weak. You would be lucky to achieve 60% line strength with it. I wonder how this one compares.

Interesting idea here:

...just as a matter of interest steps, do you use circle or "j" hooks?

Once upon a time, used to fish the standard dropper loop on a single hook with 80lb with 20 lb mono as mainline. Caught thousands of fish on these and never had one break(the knot). Fished these hand tied rigs to the point where they would often go milky from stress. Tie a second hook in below and it all changed. Its a bit like the bimini versus plait in game fishing. Some say the bimini is crap, plait is the bomb and vice versa, Me I am 100% bimini for 100% line strength proven. That is tie one back to back with about a meter separating them and break it. If you have tied it right, with the right amount of pressure for the line class, it will break within eeks of dead centre between the knots. If not keep practicing. And yes I cant tie a plait to satisfy myself so not creating an discussion here. Point is, when tying any knot perfection is only gained by repetition, confidence is only gained by use, and success is from the previous two. Just my opinion

Tied hundreds of 2 hook ledgers with the standard dropper knot. Can tie one in seconds after all the practice.Use 60lb and 80lb trace and breaking one is incredibly rare. the 10kg main line will  break first and if it a big fish it gets netted or gaffed at the boat before lifting.