With apologies to those who’ve already thought of this. 
What does it tell you, that I’m thinking of disaster recovery!
That I have disasters. But I’m learning.
I’ll call it Destination Lifeline.
I tried doing a destination row, but as I have cabled intarsia, I was having trouble. I’d pull back to the row, and then find I hadn’t stayed on the same row all the way.
Pulling back without a destination row was bad with intarsia, as it could pull out independently of the main colour.
So instead of using a needle, I did a cross between a destination row and a Lifeline, using a different coloured yarn, pulling it through each stitch with a crochet hook.
Then it was easy to see if I’d stayed on the same row all the way through, and across all colours and cables.
Only when I was sure that all looked right, I pulled back to my Destination Lifeline.
And it worked.:cheering:
I don’t know if this is a new invention, but I’m very glad that it worked for me.:happydance:
Hope someone else can make some use of this too.
Happy knitting.
Shan