"The key thing you have to remember about bacteria and eating oil is they act a lot like teenagers. They do it on their own timescale, like for a chore. They do it on their own timescale.
They usually do the easiest thing first, and they very rarely clean the whole job up. So they will play an important role in terms of our natural capacity to clean up the oil.
I wouldn't worry about science fiction aspect. When the food's gone - or in this case, you also have to remember that they'll eat the low-hanging fruit. There's some molecules that are pretty tasty, and then there are other molecules that are avoidable. And so they'll just leave them behind."
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