After all this time, I think it really did finally click.
Thank you very much Mathias for that complete explanation.
I took a closer look at the Thing Context and Target References on the wiki, and that plus the bit about "foreach thing as read-only" makes a lot more sense. all of the targets of eachthing would be for reading the tags or field values already present on the "DB definition". The only exeption to this would be the thing.amendthing[target,string] target which can only affect the name or description field, and it makes the change for ALL of the copies of that thing.
Am I understanding correctly?
And I agree that I think the simplest way to handle the "Recommended Selection" would be to change the color of the text in the table as it's being presented.