I have not experimented this in charts but what i have understood is that saturn is karma karaka so whenever saturn transits over natal saturn it kind of sets you up for next 30 years. At that particular time, you make decisions which will have a long lasting impact on your work. When saturn transits over moon it puts mental pressure so similarly i guess when saturn transits over saturn it makes you work hard physically. It would be interesting to see how saturn transit affects other planets when it transits over them for example sun,jupiter,mars etc.
Having said that i think it also depends on the strength of saturn and astakavarga points saturn is giving to that house and also strength of moon to experience anything. lol i feel nothing in astrology is black and white 😀