The burning of the oil degrades the O2 sensors. Same thing happens when an engine gets older and starts burning oil. Why would you want to do this on purpose?
Of course they are going to say it's safe for sensors! LOL SeaFoam came out long before O2 sensors were installed on vehicles. If your sensor lasts half as long using SeaFoam, you think you are going to be able to blame them for it?
Use something that actually works that has PEA in it like Techron. SeaFoam is a mixture of Oil, Naptha and Isopropyl alcohol. Gasoline already has a high percentage of naptha in it which is the only solvent in it actually doing anything.
BTW..there is no stabilizer in the world that will prevent phase separation. If you are getting enough water in your tank that you would get phase separation, you need to buy your fuel from a different source.