let's have a look at the adverse side-effects of 'mr muscle' eh?...why not....I see...oven cleaners appears to be the worst...lucky I don't have an oven, then....and yes, I can remember the advice given, now...best to move the oven outside if you can...in order to clean it...and yes I have cleaned ovens, thoroughly with specially-bought oven cleaners, over the years....at garden cottage, east bergholt, eagle house, Harwich...along with that flat in manningtree wharf...all of which were in 'real states' before I moved in...go figure:

and drain-cleaner?....go figure: