I'll tell you my personal experience on it..Sure only G knows. If they say its bad practice and against their policy i trust them and wont do such things. A penalty doesnt necessary mean you lose all of your ranks or drop hard.
penalty in my case (4 consecutive cases to be exact) meant.. I was stuck on 4 or 8 daily impressions from 1.500-2.800 a day ..
of course nothing mentioned in search console.. but it was evident that I got hit. (I recall opening a thread about it..you can look it up) of course opinions vary.. since some consider using python script on the indexing api to play a role on this... since the api's purpose is to assist different types of sites than mine were.