Exactly my worry, I use those chemicals to remove oils and dirt from parts I am cleaning. I know they are quite good are breaking up oil and dirt. I just don't want the oil washed from my bearings or other friction surfaces. I choose to pay more for ARX and LC when I KNOW they are safe. Seems stupid to risk my engine on a 4 dollar cleaner.
Just yesterday I heard an AA partsguy explaining stuff like this to a customer. Made me nervous just listening. After he explained about running Gunk and B12 in the oil he went on to say after you change oil, "add a quart of the lucas stuff, it completely keeps your oil from breaking down". By lucas he was showing the customer a bottle of the oil stabilizer.