Is polymerized oil soluble in oil?

"Burned food is bad for you." This basic tennet appears to be firmly held by [specialists](https://www.cancer.gov/about-cancer/causes-prevention/risk/diet/cooked-meats-fact-sheet).


Hence burnt food should be carefully cleaned from pots before subsequent use, and likewise on grilling equipment.


Yet the standard care for cast-iron cookware involves coating with a thin layer of oil and heating. The desirable temperature is variously indicated to be between 250F and 400F, possibly depending on the type of oil. The temperature for this reaction, polymerization, is just short of carbonization.


What is the stability of polymerized oil? Is it established whether it is soluble during subsequent cooking with new oil?


Previous relevant question(s):


* [Molecular structure](https://chemistry.stackexchange.com/q/860/34072)


