Right, an update -
The 100ml of jelly that i 'cut' with 100ml of good bio resulted in 200ml of jelly...
...but i still had hopes for it!
I put it back in a pan, water bath style, and heated it up again, and let it cool slowly (as the water retained the heat with it)
Result -
about 50ml of white soapy jelly / haze in the bottom, and 150ml of good bio on top. So, taking into account that id added 100ml of good bio, thats 50% recovery.
I then did the same again, and, sure enough, less layer at the bottom.
Ive did it one more time today, and i now have about 20ml in the bottom of the beaker. So that's 200ml, of which 100ml is the good that i added, and 80ml is the recovered.
Considering i did not take any glyc out of this batch at all, id be happy with 80% product (its certainly better than nothing!)
The 20ml now looks more like glyc than the soapy haze too. Ie its dark in colour.
I do not know the consistency of any of this, as im not shaking the beaker up at all. But the top is liquid, and, unless i have perfectly clear jelly lower down, id say its liquid to the glyc layer.
I will tip it out tomorrow to be sure.
From this test, im starting to think that, possibly, jelly batches can be cured by keeping the mix above the jelly melting point, and waiting for the soaps to settle whilst its hot. I cant do this in my processor, as the heater is inline, so i think im going to try chucking a radiator in a clip-top, and, hopefully, recovering the rest of the batch like that.